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  <xs:element id="nmslf_KWORIntermediateILLCMember" abstract="true" name="KWORIntermediateILLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_TheUltimusGroupMidcoLLCMember" abstract="true" name="TheUltimusGroupMidcoLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_BonterraLLC2Member" abstract="true" name="BonterraLLC2Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_PackagingCoordinatorsMidcoInc.2Member" abstract="true" name="PackagingCoordinatorsMidcoInc.2Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_DiamondbackAcquisitionInc.2Member" abstract="true" name="DiamondbackAcquisitionInc.2Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_FundedDebtSecuritiesMember" abstract="true" name="FundedDebtSecuritiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_FundedSecuritiesMember" abstract="true" name="FundedSecuritiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_UnfundedDebtSecuritiesMember" abstract="true" name="UnfundedDebtSecuritiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_DebtSecuritiesFirstLienMember" abstract="true" name="DebtSecuritiesFirstLienMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_DebtSecuritiesSecondLienMember" abstract="true" name="DebtSecuritiesSecondLienMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_DebtSecuritiesFloatingInterestRateMember" abstract="true" name="DebtSecuritiesFloatingInterestRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_DebtSecuritiesFixedInterestRateMember" abstract="true" name="DebtSecuritiesFixedInterestRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_BusinessServicesSectorMember" abstract="true" name="BusinessServicesSectorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_SoftwareSectorMember" abstract="true" name="SoftwareSectorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_ConsumerServicesSectorMember" abstract="true" name="ConsumerServicesSectorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_EducationSectorMember" abstract="true" name="EducationSectorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_BusinessProductsSectorMember" abstract="true" name="BusinessProductsSectorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_ConsumerProductsSectorMember" abstract="true" name="ConsumerProductsSectorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_InvestmentsAtFairValueMember" abstract="true" name="InvestmentsAtFairValueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_InvestmentTypeConcentrationRiskMember" abstract="true" name="InvestmentTypeConcentrationRiskMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_IndustryConcentrationRiskMember" abstract="true" name="IndustryConcentrationRiskMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_InterestRateTypeRiskMember" abstract="true" name="InterestRateTypeRiskMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_InvestmentCompanyNumberOfInvestmentsHeld" abstract="false" name="InvestmentCompanyNumberOfInvestmentsHeld" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="nmslf_InvestmentOwnedAtFairValueNonQualifyingAssetsPercentOfTotalAssets" abstract="false" name="InvestmentOwnedAtFairValueNonQualifyingAssetsPercentOfTotalAssets" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nmslf_RegulatoryCapitalRequirementsForInvestmentCompaniesTextBlock" abstract="false" name="RegulatoryCapitalRequirementsForInvestmentCompaniesTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="nmslf_OrganizationalExpensesPolicyPolicyTextBlock" abstract="false" name="OrganizationalExpensesPolicyPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="nmslf_NewMountainCapitalMember" abstract="true" name="NewMountainCapitalMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_InvestmentCompanyInvestmentPeriodAutomaticExtension" abstract="false" name="InvestmentCompanyInvestmentPeriodAutomaticExtension" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="nmslf_InvestmentCompanyInvestmentPeriodAutomaticExtensionOrTerminationWrittenNoticePeriodMinimum" abstract="false" name="InvestmentCompanyInvestmentPeriodAutomaticExtensionOrTerminationWrittenNoticePeriodMinimum" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="nmslf_InvestmentCompanyExpirationOfInvestmentPeriodCommencementOfWindUpOfOperationsPeriod" abstract="false" name="InvestmentCompanyExpirationOfInvestmentPeriodCommencementOfWindUpOfOperationsPeriod" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="nmslf_InvestmentCompanyExpirationOfInvestmentPeriodCommencementOfWindUpOfOperationsExtensionPeriod" abstract="false" name="InvestmentCompanyExpirationOfInvestmentPeriodCommencementOfWindUpOfOperationsExtensionPeriod" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="nmslf_InvestmentCompanyInvestmentOwnedInvestmentObjectiveMiddleMarketBusinessEBITDA" abstract="false" name="InvestmentCompanyInvestmentOwnedInvestmentObjectiveMiddleMarketBusinessEBITDA" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmslf_PercentageOfSharesHoldUnderEmployeeBenefitPlan" abstract="false" name="PercentageOfSharesHoldUnderEmployeeBenefitPlan" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="nmslf_FairValueMeasurementsQuoteDifferenceAdditionalFairValueProceduresPerformedThresholdPercentage" abstract="false" name="FairValueMeasurementsQuoteDifferenceAdditionalFairValueProceduresPerformedThresholdPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nmslf_FairValueMeasurementsSpreadBetweenBidAndAskQuoteAdditionalFairValueProceduresPerformedThresholdPercentage" abstract="false" name="FairValueMeasurementsSpreadBetweenBidAndAskQuoteAdditionalFairValueProceduresPerformedThresholdPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nmslf_InvestmentOwnedNonaccrualThresholdPeriodPastDue" abstract="false" name="InvestmentOwnedNonaccrualThresholdPeriodPastDue" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="nmslf_OrganizationalExpensesMaximumAmount" abstract="false" name="OrganizationalExpensesMaximumAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmslf_InvestmentOwnedInterestIncome" abstract="false" name="InvestmentOwnedInterestIncome" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmslf_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSalesAndSettlements" abstract="false" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSalesAndSettlements" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmslf_ValuationMarketAndIncomeApproachMember" abstract="true" name="ValuationMarketAndIncomeApproachMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_OtherValuationTechniqueMember" abstract="true" name="OtherValuationTechniqueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_InvestmentManagementAgreementMember" abstract="true" name="InvestmentManagementAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_InvestmentManagementAgreementAssetsInvestedEqualToOrLessThanThresholdMember" abstract="true" name="InvestmentManagementAgreementAssetsInvestedEqualToOrLessThanThresholdMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_InvestmentManagementAgreementAssetsInvestedGreaterThanThresholdMember" abstract="true" name="InvestmentManagementAgreementAssetsInvestedGreaterThanThresholdMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_RelatedPartyTransactionTerm" abstract="false" name="RelatedPartyTransactionTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="nmslf_ManagementAndServiceFeesBaseRateCalculationAssetsInvestedThreshold" abstract="false" name="ManagementAndServiceFeesBaseRateCalculationAssetsInvestedThreshold" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmslf_ManagementAndServiceFeesBaseRateCalculationBasedOnBlendedRateAssetsInvestedMaximum" abstract="false" name="ManagementAndServiceFeesBaseRateCalculationBasedOnBlendedRateAssetsInvestedMaximum" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nmslf_WellsCreditFacilityMember" abstract="true" name="WellsCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_LineOfCreditFacilityBorrowingCapacityFirstPercentage" abstract="false" name="LineOfCreditFacilityBorrowingCapacityFirstPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nmslf_LineOfCreditFacilityBorrowingCapacitySecondPercentage" abstract="false" name="LineOfCreditFacilityBorrowingCapacitySecondPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nmslf_LineOfCreditFacilityBorrowingCapacityThirdPercentage" abstract="false" name="LineOfCreditFacilityBorrowingCapacityThirdPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nmslf_LineOfCreditFacilityBorrowingCapacityFourthPercentage" abstract="false" name="LineOfCreditFacilityBorrowingCapacityFourthPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nmslf_FinancingCommitmentLetterToPurchaseInvestmentsMember" abstract="true" name="FinancingCommitmentLetterToPurchaseInvestmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_UnfundedDebtSecuritiesRevolvingCreditFacilitiesMember" abstract="true" name="UnfundedDebtSecuritiesRevolvingCreditFacilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_UnfundedDebtSecuritiesBridgeFacilitiesMember" abstract="true" name="UnfundedDebtSecuritiesBridgeFacilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_UnfundedDebtSecuritiesDelayedDrawsOrOtherFutureFundingCommitmentsMember" abstract="true" name="UnfundedDebtSecuritiesDelayedDrawsOrOtherFutureFundingCommitmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nmslf_InvestmentCompanyPerShareDataAbstract" abstract="true" name="InvestmentCompanyPerShareDataAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="nmslf_InvestmentCompanyRatioToAverageNetAssetsAbstract" abstract="true" name="InvestmentCompanyRatioToAverageNetAssetsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="nmslf_InvestmentCompanyExpenseRatioIncludingFeeWaiverAndReimbursements" abstract="false" name="InvestmentCompanyExpenseRatioIncludingFeeWaiverAndReimbursements" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nmslf_InvestmentCompanyContributedCapital" abstract="false" name="InvestmentCompanyContributedCapital" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
