<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019e2228-63dd-7e22-ace5-a9b4bbe0dd00,g:b5427dc4-cb80-4d5a-8814-d20f5784dc5f-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="https://xbrl.org/2023/arcrole/summation-item" xlink:type="simple" xlink:href="https://www.xbrl.org/2023/calculation-1.1.xsd#summation-item"/>
  <link:roleRef roleURI="http://www.solstice.com/role/CONSOLIDATEDSTATEMENTSOFOPERATIONSUNAUDITED" xlink:type="simple" xlink:href="sols-20260630.xsd#CONSOLIDATEDSTATEMENTSOFOPERATIONSUNAUDITED"/>
  <link:calculationLink xlink:role="http://www.solstice.com/role/CONSOLIDATEDSTATEMENTSOFOPERATIONSUNAUDITED" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_019e2228-64ac-758d-be42-ef8d9003ca15" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019e2228-64ac-7116-b19d-f47ce2f4cffa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ProfitLoss_019e2228-64ac-758d-be42-ef8d9003ca15" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019e2228-64ac-7116-b19d-f47ce2f4cffa" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019e2228-64ac-7eee-bb1e-864aa0f7858e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ProfitLoss_019e2228-64ac-758d-be42-ef8d9003ca15" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019e2228-64ac-7eee-bb1e-864aa0f7858e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_sols_CostsAndExpensesOperatingAndNonoperating_019e2228-64ac-7978-8807-da7744bf9fb4" xlink:href="sols-20260630.xsd#sols_CostsAndExpensesOperatingAndNonoperating"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_019e2228-64ac-781f-af1d-fe27bcb1e041" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_sols_CostsAndExpensesOperatingAndNonoperating_019e2228-64ac-7978-8807-da7744bf9fb4" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_019e2228-64ac-781f-af1d-fe27bcb1e041" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense_019e2228-64ac-71f9-830e-69d5de2e8a2a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResearchAndDevelopmentExpense"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_sols_CostsAndExpensesOperatingAndNonoperating_019e2228-64ac-7978-8807-da7744bf9fb4" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpense_019e2228-64ac-71f9-830e-69d5de2e8a2a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense_019e2228-64ac-7880-9a3f-da8de123897c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SellingGeneralAndAdministrativeExpense"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_sols_CostsAndExpensesOperatingAndNonoperating_019e2228-64ac-7978-8807-da7744bf9fb4" xlink:to="loc_us-gaap_SellingGeneralAndAdministrativeExpense_019e2228-64ac-7880-9a3f-da8de123897c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonrecurringExpense_019e2228-64ac-70d7-ab89-e05a758bfece" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNonrecurringExpense"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_sols_CostsAndExpensesOperatingAndNonoperating_019e2228-64ac-7978-8807-da7744bf9fb4" xlink:to="loc_us-gaap_OtherNonrecurringExpense_019e2228-64ac-70d7-ab89-e05a758bfece" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_019e2228-64ac-7511-b5ee-ce4f35a7db22" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:calculationArc order="5" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_sols_CostsAndExpensesOperatingAndNonoperating_019e2228-64ac-7978-8807-da7744bf9fb4" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_019e2228-64ac-7511-b5ee-ce4f35a7db22" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_019e2228-64ac-7b57-9bee-26a67b5b256d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_sols_CostsAndExpensesOperatingAndNonoperating_019e2228-64ac-7978-8807-da7744bf9fb4" xlink:to="loc_us-gaap_InterestExpenseNonoperating_019e2228-64ac-7b57-9bee-26a67b5b256d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019e2228-64ac-784f-951e-7559fab6c801" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019e2228-64ac-78ed-b67b-c9303d25886c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019e2228-64ac-784f-951e-7559fab6c801" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019e2228-64ac-78ed-b67b-c9303d25886c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_sols_CostsAndExpensesOperatingAndNonoperating_019e2228-64ac-7415-8eaf-0475d601e6e0" xlink:href="sols-20260630.xsd#sols_CostsAndExpensesOperatingAndNonoperating"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019e2228-64ac-784f-951e-7559fab6c801" xlink:to="loc_sols_CostsAndExpensesOperatingAndNonoperating_019e2228-64ac-7415-8eaf-0475d601e6e0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019e2228-64ac-7525-a285-aa55ef24c97e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_019e2228-64ac-7568-91aa-5938ab9a847b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_019e2228-64ac-7525-a285-aa55ef24c97e" xlink:to="loc_us-gaap_ProfitLoss_019e2228-64ac-7568-91aa-5938ab9a847b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_019e2228-64ac-7366-a73c-8b5d84ddd279" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLossAttributableToNoncontrollingInterest"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_019e2228-64ac-7525-a285-aa55ef24c97e" xlink:to="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_019e2228-64ac-7366-a73c-8b5d84ddd279" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.solstice.com/role/CONSOLIDATEDSTATEMENTSOFCOMPREHENSIVEINCOMEUNAUDITED" xlink:type="simple" xlink:href="sols-20260630.xsd#CONSOLIDATEDSTATEMENTSOFCOMPREHENSIVEINCOMEUNAUDITED"/>
  <link:calculationLink xlink:role="http://www.solstice.com/role/CONSOLIDATEDSTATEMENTSOFCOMPREHENSIVEINCOMEUNAUDITED" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019e2228-64ac-7bf9-8911-ce97c1b6cc72" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_019e2228-64ac-7f2f-abb6-f1abaca3da55" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019e2228-64ac-7bf9-8911-ce97c1b6cc72" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_019e2228-64ac-7f2f-abb6-f1abaca3da55" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_019e2228-64ac-7c97-9072-217e27ce2a85" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019e2228-64ac-7bf9-8911-ce97c1b6cc72" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_019e2228-64ac-7c97-9072-217e27ce2a85" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_019e2228-64ac-79d7-a5a7-6807beaa5c36" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019e2228-64ac-7bf9-8911-ce97c1b6cc72" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_019e2228-64ac-79d7-a5a7-6807beaa5c36" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_019e2228-64ac-76f6-b0ab-a92d802893f2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax_019e2228-64ac-77a7-a12c-3e25337507ae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_019e2228-64ac-76f6-b0ab-a92d802893f2" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax_019e2228-64ac-77a7-a12c-3e25337507ae" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax_019e2228-64ac-7fdb-9026-188afce008f1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_019e2228-64ac-76f6-b0ab-a92d802893f2" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax_019e2228-64ac-7fdb-9026-188afce008f1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_019e2228-64ac-7ec6-8d88-02ef979deadb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_019e2228-64ac-7942-8141-364a541a4da0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_019e2228-64ac-7ec6-8d88-02ef979deadb" xlink:to="loc_us-gaap_ProfitLoss_019e2228-64ac-7942-8141-364a541a4da0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019e2228-64ac-7769-b5bf-39e876b93b62" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_019e2228-64ac-7ec6-8d88-02ef979deadb" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019e2228-64ac-7769-b5bf-39e876b93b62" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.solstice.com/role/CONSOLIDATEDBALANCESHEETSUNAUDITED" xlink:type="simple" xlink:href="sols-20260630.xsd#CONSOLIDATEDBALANCESHEETSUNAUDITED"/>
  <link:calculationLink xlink:role="http://www.solstice.com/role/CONSOLIDATEDBALANCESHEETSUNAUDITED" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019e2228-64ac-762a-91d6-b0173207c1b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019e2228-64ac-7506-b621-04026f82838c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019e2228-64ac-762a-91d6-b0173207c1b6" xlink:to="loc_us-gaap_StockholdersEquity_019e2228-64ac-7506-b621-04026f82838c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterest_019e2228-64ac-7142-a53c-96447a2e2275" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterest"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019e2228-64ac-762a-91d6-b0173207c1b6" xlink:to="loc_us-gaap_MinorityInterest_019e2228-64ac-7142-a53c-96447a2e2275" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_019e2228-64ac-7f4f-b742-0d7323f70676" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableCurrent_019e2228-64ac-707f-8b7d-b0af6f54f770" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019e2228-64ac-7f4f-b742-0d7323f70676" xlink:to="loc_us-gaap_AccountsPayableCurrent_019e2228-64ac-707f-8b7d-b0af6f54f770" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityCurrent_019e2228-64ac-71d2-83b3-643485970785" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019e2228-64ac-7f4f-b742-0d7323f70676" xlink:to="loc_us-gaap_FinanceLeaseLiabilityCurrent_019e2228-64ac-71d2-83b3-643485970785" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtCurrent_019e2228-64ac-7ede-825e-2e4d192deb86" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019e2228-64ac-7f4f-b742-0d7323f70676" xlink:to="loc_us-gaap_LongTermDebtCurrent_019e2228-64ac-7ede-825e-2e4d192deb86" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_sols_ProductLoansPayableCurrent_019e2228-64ac-783d-a818-eeac587c8000" xlink:href="sols-20260630.xsd#sols_ProductLoansPayableCurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019e2228-64ac-7f4f-b742-0d7323f70676" xlink:to="loc_sols_ProductLoansPayableCurrent_019e2228-64ac-783d-a818-eeac587c8000" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_sols_AccruedAndOtherLiabilitiesCurrent_019e2228-64ac-741e-9eb2-af67541648db" xlink:href="sols-20260630.xsd#sols_AccruedAndOtherLiabilitiesCurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019e2228-64ac-7f4f-b742-0d7323f70676" xlink:to="loc_sols_AccruedAndOtherLiabilitiesCurrent_019e2228-64ac-741e-9eb2-af67541648db" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019e2228-64ac-7574-8559-eec6acbe6a7b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_019e2228-64ac-7587-a211-f85b6deb9f09" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019e2228-64ac-7574-8559-eec6acbe6a7b" xlink:to="loc_us-gaap_AssetsCurrent_019e2228-64ac-7587-a211-f85b6deb9f09" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_019e2228-64ac-7056-800e-5c0580d155b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Goodwill"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019e2228-64ac-7574-8559-eec6acbe6a7b" xlink:to="loc_us-gaap_Goodwill_019e2228-64ac-7056-800e-5c0580d155b6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019e2228-64ac-7e13-9b06-4b6b33c3fb83" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019e2228-64ac-7574-8559-eec6acbe6a7b" xlink:to="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019e2228-64ac-7e13-9b06-4b6b33c3fb83" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxAssetsNet_019e2228-64ac-7801-ad9c-743a5f22e7e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxAssetsNet"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019e2228-64ac-7574-8559-eec6acbe6a7b" xlink:to="loc_us-gaap_DeferredIncomeTaxAssetsNet_019e2228-64ac-7801-ad9c-743a5f22e7e0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_019e2228-64ac-765f-9897-ae292d131290" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestments"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019e2228-64ac-7574-8559-eec6acbe6a7b" xlink:to="loc_us-gaap_EquityMethodInvestments_019e2228-64ac-765f-9897-ae292d131290" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_019e2228-64ac-769d-91a7-f34fcf773a7e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsNoncurrent"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019e2228-64ac-7574-8559-eec6acbe6a7b" xlink:to="loc_us-gaap_OtherAssetsNoncurrent_019e2228-64ac-769d-91a7-f34fcf773a7e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_019e2228-64ac-70ab-8923-f2c271af76cb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019e2228-64ac-7574-8559-eec6acbe6a7b" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_019e2228-64ac-70ab-8923-f2c271af76cb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019e2228-64ac-7374-8ff4-f5bdbbc8e54b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_019e2228-64ac-7f4c-b953-37830e13ba85" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019e2228-64ac-7374-8ff4-f5bdbbc8e54b" xlink:to="loc_us-gaap_LiabilitiesCurrent_019e2228-64ac-7f4c-b953-37830e13ba85" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxLiabilitiesNet_019e2228-64ac-7cd7-9806-558ab67f8f4c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxLiabilitiesNet"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019e2228-64ac-7374-8ff4-f5bdbbc8e54b" xlink:to="loc_us-gaap_DeferredIncomeTaxLiabilitiesNet_019e2228-64ac-7cd7-9806-558ab67f8f4c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityNoncurrent_019e2228-64ac-7f0b-af2e-9697f63e343c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiabilityNoncurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019e2228-64ac-7374-8ff4-f5bdbbc8e54b" xlink:to="loc_us-gaap_FinanceLeaseLiabilityNoncurrent_019e2228-64ac-7f0b-af2e-9697f63e343c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_019e2228-64ac-757a-af14-9c0485b92b29" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilitiesNoncurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019e2228-64ac-7374-8ff4-f5bdbbc8e54b" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrent_019e2228-64ac-757a-af14-9c0485b92b29" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_019e2228-64ac-7494-ba40-68699d8155c7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtNoncurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019e2228-64ac-7374-8ff4-f5bdbbc8e54b" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_019e2228-64ac-7494-ba40-68699d8155c7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_sols_ProductLoansPayableNoncurrent_019e2228-64ac-753d-a4db-8c851670f007" xlink:href="sols-20260630.xsd#sols_ProductLoansPayableNoncurrent"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_019e2228-64ac-7374-8ff4-f5bdbbc8e54b" xlink:to="loc_sols_ProductLoansPayableNoncurrent_019e2228-64ac-753d-a4db-8c851670f007" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019e2228-64ac-7866-a0ed-8625eaa303ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_019e2228-64ac-73b3-bf32-68d4e4478f9e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_019e2228-64ac-7866-a0ed-8625eaa303ee" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_019e2228-64ac-73b3-bf32-68d4e4478f9e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValue_019e2228-64ac-7b28-9a41-d0c14b9ee721" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockValue"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_019e2228-64ac-7866-a0ed-8625eaa303ee" xlink:to="loc_us-gaap_CommonStockValue_019e2228-64ac-7b28-9a41-d0c14b9ee721" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapital_019e2228-64ac-74bc-a87f-fbb61a351edd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapital"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_019e2228-64ac-7866-a0ed-8625eaa303ee" xlink:to="loc_us-gaap_AdditionalPaidInCapital_019e2228-64ac-74bc-a87f-fbb61a351edd" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_019e2228-64ac-7796-a7ac-18d7941b6de6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_019e2228-64ac-7866-a0ed-8625eaa303ee" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_019e2228-64ac-7796-a7ac-18d7941b6de6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_019e2228-64ac-7057-9b77-2ddf284b926e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019e2228-64ac-7ad0-81a0-9f17a1e9c1ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019e2228-64ac-7057-9b77-2ddf284b926e" xlink:to="loc_us-gaap_Liabilities_019e2228-64ac-7ad0-81a0-9f17a1e9c1ab" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsAndContingencies_019e2228-64ac-7278-9c6f-7be6603d5ef4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommitmentsAndContingencies"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019e2228-64ac-7057-9b77-2ddf284b926e" xlink:to="loc_us-gaap_CommitmentsAndContingencies_019e2228-64ac-7278-9c6f-7be6603d5ef4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019e2228-64ac-78a7-8352-83a9850d2c23" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019e2228-64ac-7057-9b77-2ddf284b926e" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019e2228-64ac-78a7-8352-83a9850d2c23" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_019e2228-64ac-75ee-9eb3-166fd2d1b5b7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019e2228-64ac-763b-902b-cf7e7d68d9eb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019e2228-64ac-75ee-9eb3-166fd2d1b5b7" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019e2228-64ac-763b-902b-cf7e7d68d9eb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_019e2228-64ac-72f5-99a7-3feb8ca44293" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019e2228-64ac-75ee-9eb3-166fd2d1b5b7" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_019e2228-64ac-72f5-99a7-3feb8ca44293" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNet_019e2228-64ac-781d-b8d3-b2b51250d54d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryNet"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019e2228-64ac-75ee-9eb3-166fd2d1b5b7" xlink:to="loc_us-gaap_InventoryNet_019e2228-64ac-781d-b8d3-b2b51250d54d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsCurrent_019e2228-64ac-7e1e-a82c-e6183fe3810a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsCurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019e2228-64ac-75ee-9eb3-166fd2d1b5b7" xlink:to="loc_us-gaap_OtherAssetsCurrent_019e2228-64ac-7e1e-a82c-e6183fe3810a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_sols_ProductLoansReceivableCurrent_019e2228-64ac-7106-aa6e-0cd02711bda0" xlink:href="sols-20260630.xsd#sols_ProductLoansReceivableCurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019e2228-64ac-75ee-9eb3-166fd2d1b5b7" xlink:to="loc_sols_ProductLoansReceivableCurrent_019e2228-64ac-7106-aa6e-0cd02711bda0" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.solstice.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWSUNAUDITED" xlink:type="simple" xlink:href="sols-20260630.xsd#CONSOLIDATEDSTATEMENTSOFCASHFLOWSUNAUDITED"/>
  <link:calculationLink xlink:role="http://www.solstice.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWSUNAUDITED" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019e2228-64ac-72a3-8774-400e6c04e7f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7c97-a037-cad9726d687a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019e2228-64ac-72a3-8774-400e6c04e7f8" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7c97-a037-cad9726d687a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019e2228-64ac-769b-aa75-cbd729397bd1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019e2228-64ac-72a3-8774-400e6c04e7f8" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019e2228-64ac-769b-aa75-cbd729397bd1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019e2228-64ac-7b06-80b2-e74b611116b1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019e2228-64ac-72a3-8774-400e6c04e7f8" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019e2228-64ac-7b06-80b2-e74b611116b1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_019e2228-64ac-727e-82ce-cb654b1c0150" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019e2228-64ac-72a3-8774-400e6c04e7f8" xlink:to="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_019e2228-64ac-727e-82ce-cb654b1c0150" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019e2228-64ac-7423-81a3-73be575dbcbd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_019e2228-64ac-701c-a8ca-338d12f39153" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019e2228-64ac-7423-81a3-73be575dbcbd" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_019e2228-64ac-701c-a8ca-338d12f39153" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_sols_PaymentsForLifeLongCatalystsAndDeferredMaintenance_019e2228-64ac-78f7-a62b-942e42a21019" xlink:href="sols-20260630.xsd#sols_PaymentsForLifeLongCatalystsAndDeferredMaintenance"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019e2228-64ac-7423-81a3-73be575dbcbd" xlink:to="loc_sols_PaymentsForLifeLongCatalystsAndDeferredMaintenance_019e2228-64ac-78f7-a62b-942e42a21019" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_019e2228-64ac-7ec2-a8d7-6e8c5a515e5b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019e2228-64ac-7423-81a3-73be575dbcbd" xlink:to="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_019e2228-64ac-7ec2-a8d7-6e8c5a515e5b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForSoftware_019e68aa-e61e-79f8-ad33-ce2c5b18b592" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForSoftware"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019e2228-64ac-7423-81a3-73be575dbcbd" xlink:to="loc_us-gaap_PaymentsForSoftware_019e68aa-e61e-79f8-ad33-ce2c5b18b592" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_019e2228-64ac-715b-ad15-51b4dbe9f155" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:to="loc_us-gaap_ProfitLoss_019e2228-64ac-715b-ad15-51b4dbe9f155" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Depreciation_019e2228-64ac-7f9f-8ef6-e4049092fe47" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Depreciation"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:to="loc_us-gaap_Depreciation_019e2228-64ac-7f9f-8ef6-e4049092fe47" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentForAmortization_019e2228-64ac-7af8-b572-2cb555e0a1b7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentForAmortization"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:to="loc_us-gaap_AdjustmentForAmortization_019e2228-64ac-7af8-b572-2cb555e0a1b7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions_019e2228-64ac-797b-86b7-7e0e035f6561" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions_019e2228-64ac-797b-86b7-7e0e035f6561" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfPropertyPlantEquipment_019e2228-64ac-7845-aad3-4029dc1ed24d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnSaleOfPropertyPlantEquipment"/>
    <link:calculationArc order="5" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:to="loc_us-gaap_GainLossOnSaleOfPropertyPlantEquipment_019e2228-64ac-7845-aad3-4029dc1ed24d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_019e2228-64ac-76fb-a722-024f12c34366" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensation"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:to="loc_us-gaap_ShareBasedCompensation_019e2228-64ac-76fb-a722-024f12c34366" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInDeferredIncomeTaxes_019e2228-64ac-735c-b9da-6e0565d1a69a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInDeferredIncomeTaxes"/>
    <link:calculationArc order="7" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:to="loc_us-gaap_IncreaseDecreaseInDeferredIncomeTaxes_019e2228-64ac-735c-b9da-6e0565d1a69a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_019e2228-64ac-7fb8-9622-86956d39ab91" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable"/>
    <link:calculationArc order="8" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_019e2228-64ac-7fb8-9622-86956d39ab91" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInInventories_019e2228-64ac-7299-b787-981847c67ea8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInInventories"/>
    <link:calculationArc order="9" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:to="loc_us-gaap_IncreaseDecreaseInInventories_019e2228-64ac-7299-b787-981847c67ea8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets_019e2228-64ac-7a39-8368-3af4b6ef0e59" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherOperatingAssets"/>
    <link:calculationArc order="10" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets_019e2228-64ac-7a39-8368-3af4b6ef0e59" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayable_019e2228-64ac-763a-9070-b1cd01a0cfe5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsPayable"/>
    <link:calculationArc order="11" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsPayable_019e2228-64ac-763a-9070-b1cd01a0cfe5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherAccruedLiabilities_019e2228-64ac-72b1-a1d2-fcba94888a15" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherAccruedLiabilities"/>
    <link:calculationArc order="12" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherAccruedLiabilities_019e2228-64ac-72b1-a1d2-fcba94888a15" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability_019e2228-64ac-717a-a8ee-b63ce4868012" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerLiability"/>
    <link:calculationArc order="13" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:to="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability_019e2228-64ac-717a-a8ee-b63ce4868012" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_019e2228-64ac-7d05-ba03-6453bd53fe6b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities"/>
    <link:calculationArc order="14" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019e2228-64ac-7e79-8dfa-1045a3e55e51" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_019e2228-64ac-7d05-ba03-6453bd53fe6b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019e2228-64ac-7324-9164-167216f4d150" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_sols_ProceedsFromPaymentsForParentFinancingActivities_019e2228-64ac-7641-8605-5106b6793768" xlink:href="sols-20260630.xsd#sols_ProceedsFromPaymentsForParentFinancingActivities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019e2228-64ac-7324-9164-167216f4d150" xlink:to="loc_sols_ProceedsFromPaymentsForParentFinancingActivities_019e2228-64ac-7641-8605-5106b6793768" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDividends_019e2228-64ac-731e-adb9-b52cab1e97b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsOfDividends"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019e2228-64ac-7324-9164-167216f4d150" xlink:to="loc_us-gaap_PaymentsOfDividends_019e2228-64ac-731e-adb9-b52cab1e97b6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeasePrincipalPayments_019e2228-64ac-7f94-8805-c23198bf5a26" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeasePrincipalPayments"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019e2228-64ac-7324-9164-167216f4d150" xlink:to="loc_us-gaap_FinanceLeasePrincipalPayments_019e2228-64ac-7f94-8805-c23198bf5a26" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.solstice.com/role/RevenueRecognitionandContractswithCustomersScheduleofContractBalancesDetails" xlink:type="simple" xlink:href="sols-20260630.xsd#RevenueRecognitionandContractswithCustomersScheduleofContractBalancesDetails"/>
  <link:calculationLink xlink:role="http://www.solstice.com/role/RevenueRecognitionandContractswithCustomersScheduleofContractBalancesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_sols_ContractWithCustomerAssetsLiabilitiesIncreaseDecrease_019e2228-64ac-76a0-aeaa-f615bb0665ac" xlink:href="sols-20260630.xsd#sols_ContractWithCustomerAssetsLiabilitiesIncreaseDecrease"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInContractWithCustomerAsset_019e2228-64ac-7ce3-b026-f8a8fcaa3ef8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerAsset"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_sols_ContractWithCustomerAssetsLiabilitiesIncreaseDecrease_019e2228-64ac-76a0-aeaa-f615bb0665ac" xlink:to="loc_us-gaap_IncreaseDecreaseInContractWithCustomerAsset_019e2228-64ac-7ce3-b026-f8a8fcaa3ef8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability_019e2228-64ac-7789-bce7-fa4df1f34280" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerLiability"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_sols_ContractWithCustomerAssetsLiabilitiesIncreaseDecrease_019e2228-64ac-76a0-aeaa-f615bb0665ac" xlink:to="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability_019e2228-64ac-7789-bce7-fa4df1f34280" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.solstice.com/role/InventoriesDetails" xlink:type="simple" xlink:href="sols-20260630.xsd#InventoriesDetails"/>
  <link:calculationLink xlink:role="http://www.solstice.com/role/InventoriesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNet_019e2228-64ac-70d0-9f29-f821fa1d4ed8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryRawMaterialsAndSupplies_019e2228-64ac-777c-b730-1d5518b31775" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryRawMaterialsAndSupplies"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_019e2228-64ac-70d0-9f29-f821fa1d4ed8" xlink:to="loc_us-gaap_InventoryRawMaterialsAndSupplies_019e2228-64ac-777c-b730-1d5518b31775" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryWorkInProcess_019e2228-64ac-7082-bb81-e8f30617ee45" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryWorkInProcess"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_019e2228-64ac-70d0-9f29-f821fa1d4ed8" xlink:to="loc_us-gaap_InventoryWorkInProcess_019e2228-64ac-7082-bb81-e8f30617ee45" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryFinishedGoods_019e2228-64ac-7887-bc71-05a421e7917f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryFinishedGoods"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_019e2228-64ac-70d0-9f29-f821fa1d4ed8" xlink:to="loc_us-gaap_InventoryFinishedGoods_019e2228-64ac-7887-bc71-05a421e7917f" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.solstice.com/role/GoodwillandOtherIntangibleAssetsNetScheduleofIntangibleAssetsDetails" xlink:type="simple" xlink:href="sols-20260630.xsd#GoodwillandOtherIntangibleAssetsNetScheduleofIntangibleAssetsDetails"/>
  <link:calculationLink xlink:role="http://www.solstice.com/role/GoodwillandOtherIntangibleAssetsNetScheduleofIntangibleAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019e2228-64ac-7ad1-bf0f-30914dbe4035" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019e2228-64ac-759b-a43d-323c8acf14fc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019e2228-64ac-7ad1-bf0f-30914dbe4035" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019e2228-64ac-759b-a43d-323c8acf14fc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019e2228-64ac-7204-94ae-e76d8fc36b4e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019e2228-64ac-7ad1-bf0f-30914dbe4035" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019e2228-64ac-7204-94ae-e76d8fc36b4e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_019e2228-64ac-73e0-81c5-9f38994b0154" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntangibleAssetsGrossExcludingGoodwill"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019e2228-64ac-764f-83c1-dd36763cf344" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_019e2228-64ac-73e0-81c5-9f38994b0154" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019e2228-64ac-764f-83c1-dd36763cf344" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_019e2228-64ac-77d0-b4f3-1deec80c387b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_019e2228-64ac-73e0-81c5-9f38994b0154" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_019e2228-64ac-77d0-b4f3-1deec80c387b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019e2228-64ac-70ff-b2b4-34e23ba327ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019e2228-64ac-7888-9aff-9a53222691e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019e2228-64ac-70ff-b2b4-34e23ba327ac" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019e2228-64ac-7888-9aff-9a53222691e6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_019e2228-64ac-721c-b2df-e2e6e0bd57e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019e2228-64ac-70ff-b2b4-34e23ba327ac" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_019e2228-64ac-721c-b2df-e2e6e0bd57e6" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.solstice.com/role/GoodwillandOtherIntangibleAssetsNetScheduleofIntangibleAssetsDetails_1" xlink:type="simple" xlink:href="sols-20260630.xsd#GoodwillandOtherIntangibleAssetsNetScheduleofIntangibleAssetsDetails_1"/>
  <link:calculationLink xlink:role="http://www.solstice.com/role/GoodwillandOtherIntangibleAssetsNetScheduleofIntangibleAssetsDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019e2228-64ac-7e73-b959-eed9e47a0ee7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_019e2228-64ac-7ed7-ae3c-6c71cf187850" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntangibleAssetsGrossExcludingGoodwill"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019e2228-64ac-7e73-b959-eed9e47a0ee7" xlink:to="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_019e2228-64ac-7ed7-ae3c-6c71cf187850" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019e2228-64ac-7b06-9ec5-ab86d74f901f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019e2228-64ac-7e73-b959-eed9e47a0ee7" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019e2228-64ac-7b06-9ec5-ab86d74f901f" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.solstice.com/role/DebtScheduleofComponentsofDebtDetails" xlink:type="simple" xlink:href="sols-20260630.xsd#DebtScheduleofComponentsofDebtDetails"/>
  <link:calculationLink xlink:role="http://www.solstice.com/role/DebtScheduleofComponentsofDebtDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_019e2228-64ac-79f9-a6cd-6272e4e92f97" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_019e2228-64ac-774f-bd70-ea58d7b142b8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_019e2228-64ac-79f9-a6cd-6272e4e92f97" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_019e2228-64ac-774f-bd70-ea58d7b142b8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiability_019e2228-64ac-7ffa-a6e8-cb6db75247eb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiability"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_019e2228-64ac-79f9-a6cd-6272e4e92f97" xlink:to="loc_us-gaap_FinanceLeaseLiability_019e2228-64ac-7ffa-a6e8-cb6db75247eb" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.solstice.com/role/FairValueMeasurementsScheduleofFairValueofFinancialAssetsDetails" xlink:type="simple" xlink:href="sols-20260630.xsd#FairValueMeasurementsScheduleofFairValueofFinancialAssetsDetails"/>
  <link:calculationLink xlink:role="http://www.solstice.com/role/FairValueMeasurementsScheduleofFairValueofFinancialAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_019e2228-64ac-776d-bcf4-777febe58938" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableFairValueDisclosure_019e2228-64ac-73ef-b905-ead25adcd9aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoansReceivableFairValueDisclosure"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsFairValueDisclosure_019e2228-64ac-776d-bcf4-777febe58938" xlink:to="loc_us-gaap_LoansReceivableFairValueDisclosure_019e2228-64ac-73ef-b905-ead25adcd9aa" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_019e2228-64ac-735f-9f1a-168014c13927" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesFairValueDisclosure"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansPayableFairValueDisclosure_019e2228-64ac-705a-ac50-5002df13f062" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoansPayableFairValueDisclosure"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosure_019e2228-64ac-735f-9f1a-168014c13927" xlink:to="loc_us-gaap_LoansPayableFairValueDisclosure_019e2228-64ac-705a-ac50-5002df13f062" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.solstice.com/role/EarningsPerShareScheduleofBasicandDilutedEarningsPerShareDetails" xlink:type="simple" xlink:href="sols-20260630.xsd#EarningsPerShareScheduleofBasicandDilutedEarningsPerShareDetails"/>
  <link:calculationLink xlink:role="http://www.solstice.com/role/EarningsPerShareScheduleofBasicandDilutedEarningsPerShareDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019e2228-64ac-718c-bb83-7c68f59f4621" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_019e2228-64ac-7008-9856-d86e8093f6d8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019e2228-64ac-718c-bb83-7c68f59f4621" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_019e2228-64ac-7008-9856-d86e8093f6d8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_019e2228-64ac-771d-bace-624f190ca4f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019e2228-64ac-718c-bb83-7c68f59f4621" xlink:to="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_019e2228-64ac-771d-bace-624f190ca4f9" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.solstice.com/role/SegmentFinancialDataScheduleofReconciliationofSalesandEBITDADetails" xlink:type="simple" xlink:href="sols-20260630.xsd#SegmentFinancialDataScheduleofReconciliationofSalesandEBITDADetails"/>
  <link:calculationLink xlink:role="http://www.solstice.com/role/SegmentFinancialDataScheduleofReconciliationofSalesandEBITDADetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_019e2228-6573-7541-ae66-20482957e98e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_sols_EarningsBeforeInterestTaxDepreciationAndAmortization_019e2228-6573-7fb3-976c-d8655d88e567" xlink:href="sols-20260630.xsd#sols_EarningsBeforeInterestTaxDepreciationAndAmortization"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ProfitLoss_019e2228-6573-7541-ae66-20482957e98e" xlink:to="loc_sols_EarningsBeforeInterestTaxDepreciationAndAmortization_019e2228-6573-7fb3-976c-d8655d88e567" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Depreciation_019e2228-6573-7d56-bbe1-b5c89e1745b2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Depreciation"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ProfitLoss_019e2228-6573-7541-ae66-20482957e98e" xlink:to="loc_us-gaap_Depreciation_019e2228-6573-7d56-bbe1-b5c89e1745b2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentForAmortization_019e2228-6573-7698-afd4-1399a1b9ed6d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentForAmortization"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ProfitLoss_019e2228-6573-7541-ae66-20482957e98e" xlink:to="loc_us-gaap_AdjustmentForAmortization_019e2228-6573-7698-afd4-1399a1b9ed6d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_019e2228-6573-7087-838b-7a784d500445" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ProfitLoss_019e2228-6573-7541-ae66-20482957e98e" xlink:to="loc_us-gaap_InterestExpenseNonoperating_019e2228-6573-7087-838b-7a784d500445" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingOtherItemAmount_019e2228-6573-71d6-9bd8-991879515d28" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingOtherItemAmount"/>
    <link:calculationArc order="5" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ProfitLoss_019e2228-6573-7541-ae66-20482957e98e" xlink:to="loc_us-gaap_SegmentReportingOtherItemAmount_019e2228-6573-71d6-9bd8-991879515d28" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_019e2228-6573-7155-a2cf-c7325b1d2fe8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ProfitLoss_019e2228-6573-7541-ae66-20482957e98e" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_019e2228-6573-7155-a2cf-c7325b1d2fe8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonrecurringExpense_019e2228-6573-76d9-8714-df1f4da72ab3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNonrecurringExpense"/>
    <link:calculationArc order="7" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ProfitLoss_019e2228-6573-7541-ae66-20482957e98e" xlink:to="loc_us-gaap_OtherNonrecurringExpense_019e2228-6573-76d9-8714-df1f4da72ab3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019e2228-6573-7132-9f25-2e7e46420f1c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:calculationArc order="8" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ProfitLoss_019e2228-6573-7541-ae66-20482957e98e" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019e2228-6573-7132-9f25-2e7e46420f1c" xlink:type="arc"/>
  </link:calculationLink>
</link:linkbase>
