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  <xsd:element name="NumberOfWarrantsPerUnit" id="imsr_NumberOfWarrantsPerUnit" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ClassOfWarrantOrRightExercisableExercisePriceOfWarrantsOrRights" id="imsr_ClassOfWarrantOrRightExercisableExercisePriceOfWarrantsOrRights" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="DebtConversionIssuanceOfAdditionalSecuritiesThresholdPeriodAfterExpiryOfLockUps" id="imsr_DebtConversionIssuanceOfAdditionalSecuritiesThresholdPeriodAfterExpiryOfLockUps" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DebtConversionIssuanceOfAdditionalSecuritiesFloorPrice" id="imsr_DebtConversionIssuanceOfAdditionalSecuritiesFloorPrice" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DebtInstrumentAutomaticConversionThresholdIssuanceOfCommonOrPreferredShares" id="imsr_DebtInstrumentAutomaticConversionThresholdIssuanceOfCommonOrPreferredShares" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="DebtInstrumentDiscount" id="imsr_DebtInstrumentDiscount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DebtInstrumentForeignCurrencyTranslationAdjustment" id="imsr_DebtInstrumentForeignCurrencyTranslationAdjustment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="PreferredExchangeableStockMember" id="imsr_PreferredExchangeableStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CommonExchangeableStockMember" id="imsr_CommonExchangeableStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AdjustmentsToAdditionalPaidInCapitalGainLossOnExtinguishmentOfDebt" id="imsr_AdjustmentsToAdditionalPaidInCapitalGainLossOnExtinguishmentOfDebt" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="InterestPayableNoncurrent" id="imsr_InterestPayableNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="OrganizationConsolidationAndPresentationOfFinancialStatementsTable" id="imsr_OrganizationConsolidationAndPresentationOfFinancialStatementsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TerrestrialEnergyDelawareIncMember" id="imsr_TerrestrialEnergyDelawareIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TerrestrialEnergyCanadaExchangeIncMember" id="imsr_TerrestrialEnergyCanadaExchangeIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ExtinguishmentOfDebtAmountRelatedParty" id="imsr_ExtinguishmentOfDebtAmountRelatedParty" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="RecognitionOfWarrantsInConnectionWithConvertibleNotesNetOfTax" id="imsr_RecognitionOfWarrantsInConnectionWithConvertibleNotesNetOfTax" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AcquisitionOfNonControllingInterest" id="imsr_AcquisitionOfNonControllingInterest" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PrepaidExpensesAndOtherCurrentAssetsTextBlock" id="imsr_PrepaidExpensesAndOtherCurrentAssetsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LeaseDisclosureTextBlock" id="imsr_LeaseDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ResearchAndDevelopmentTaxCreditsPolicyPolicyTextBlock" id="imsr_ResearchAndDevelopmentTaxCreditsPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ScheduleOfPropertyPlantAndEquipmentUsefulLifeTableTextBlock" id="imsr_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ResearchAndDevelopmentTaxCredits" id="imsr_ResearchAndDevelopmentTaxCredits" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="PrepaidSoftwareCosts" id="imsr_PrepaidSoftwareCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ComputerSoftwareMember" id="imsr_ComputerSoftwareMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IntellectualPropertyRightsMember" id="imsr_IntellectualPropertyRightsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PatentsAndTrademarksMember" id="imsr_PatentsAndTrademarksMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AccruedContractorExpenseCurrent" id="imsr_AccruedContractorExpenseCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AccruedGovernmentGrantRepaymentCurrent" id="imsr_AccruedGovernmentGrantRepaymentCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="GovernmentAssistanceRepaymentMultiplier" id="imsr_GovernmentAssistanceRepaymentMultiplier" type="xbrli:pureItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="GovernmentAssistanceAnnualRepaymentRateToRevenue" id="imsr_GovernmentAssistanceAnnualRepaymentRateToRevenue" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationPermanentTaxDifferencesPercent" id="imsr_EffectiveIncomeTaxRateReconciliationPermanentTaxDifferencesPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationReturnToProvisionAdjustmentsPercent" id="imsr_EffectiveIncomeTaxRateReconciliationReturnToProvisionAdjustmentsPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationForeignExchangeChangesPercent" id="imsr_EffectiveIncomeTaxRateReconciliationForeignExchangeChangesPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DeferredTaxAssetResearchAndDevelopmentExpenses" id="imsr_DeferredTaxAssetResearchAndDevelopmentExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DeferredTaxAssetsOperatingLeaseLiabilities" id="imsr_DeferredTaxAssetsOperatingLeaseLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="OperatingLossCarryforwardsExpirationPeriod" id="imsr_OperatingLossCarryforwardsExpirationPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="TaxCreditCarryforwardExpirationPeriod" id="imsr_TaxCreditCarryforwardExpirationPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ExchangeableStockValueIssued" id="imsr_ExchangeableStockValueIssued" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ExchangeableStockParOrStatedValuePerShare" id="imsr_ExchangeableStockParOrStatedValuePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ExchangeableStockSharesIssued" id="imsr_ExchangeableStockSharesIssued" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ExchangeableStockSharesOutstanding" id="imsr_ExchangeableStockSharesOutstanding" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="DeferredTaxAssetResearchAndDevelopmentIntangibles" id="imsr_DeferredTaxAssetResearchAndDevelopmentIntangibles" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="CommonStockNumberOfVotesPerShare" id="imsr_CommonStockNumberOfVotesPerShare" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IncreaseDecreaseInInterestPayableNonCurrent" id="imsr_IncreaseDecreaseInInterestPayableNonCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PaymentOfMergerAndRecapitalizationRelatedTransactionCosts" id="imsr_PaymentOfMergerAndRecapitalizationRelatedTransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="FinanceLeasesRecognized" id="imsr_FinanceLeasesRecognized" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="FinancialInstrumentsAbstract" id="imsr_FinancialInstrumentsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ProceedsFromIssuanceOfPrivatePlacementGross" id="imsr_ProceedsFromIssuanceOfPrivatePlacementGross" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ProceedsFromTrustAccountNetOfRedemption" id="imsr_ProceedsFromTrustAccountNetOfRedemption" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="TrustAccountRedemptionPercentage" id="imsr_TrustAccountRedemptionPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardConversionRatio" id="imsr_ShareBasedCompensationArrangementByShareBasedPaymentAwardConversionRatio" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="LiquidityAndGoingConcernPolicyTextBlock" id="imsr_LiquidityAndGoingConcernPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="CashCashEquivalentAndMarketableSecurityPolicyTextBlock" id="imsr_CashCashEquivalentAndMarketableSecurityPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ReverseRecapitalizationAbstract" id="imsr_ReverseRecapitalizationAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ReverseRecapitalizationDisclosureTextBlock" id="imsr_ReverseRecapitalizationDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ScheduleOfReconciliationOfElementsOfBusinessCombinationToStatementOfCashFlowsAndStatementOfChangesInEquityTableTextBlock" id="imsr_ScheduleOfReconciliationOfElementsOfBusinessCombinationToStatementOfCashFlowsAndStatementOfChangesInEquityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ScheduleOfNumberOfCommonStockOutstandingAfterBusinessCombinationTableTextBlock" id="imsr_ScheduleOfNumberOfCommonStockOutstandingAfterBusinessCombinationTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ScheduleOfRecapitalizationExpensesTableTextBlock" id="imsr_ScheduleOfRecapitalizationExpensesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ReverseRecapitalizationTable" id="imsr_ReverseRecapitalizationTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ReverseRecapitalizationLineItems" id="imsr_ReverseRecapitalizationLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ReverseRecapitalizationExpensesAbstract" id="imsr_ReverseRecapitalizationExpensesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TotalOrdinarySharesIssued" id="imsr_TotalOrdinarySharesIssued" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="TotalExchangeableStockSharesIssued" id="imsr_TotalExchangeableStockSharesIssued" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="AggregateSharesIssuedRecasted" id="imsr_AggregateSharesIssuedRecasted" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ProceedsFromBusinessCombinationNet" id="imsr_ProceedsFromBusinessCombinationNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AggregateExchangeableSharesRecasted" id="imsr_AggregateExchangeableSharesRecasted" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ShortTermInvestmentsAmortizedCost" id="imsr_ShortTermInvestmentsAmortizedCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ConversionOfPreferredExchangeableSharesToExchangeableShares" id="imsr_ConversionOfPreferredExchangeableSharesToExchangeableShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ConversionOfCommonExchangeableSharesToExchangeableShares" id="imsr_ConversionOfCommonExchangeableSharesToExchangeableShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="Rule10b51ArrangementModifiedFlag" id="imsr_Rule10b51ArrangementModifiedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NonRule10b51ArrangementModifiedFlag" id="imsr_NonRule10b51ArrangementModifiedFlag" type="xbrli:booleanItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="IncomeTaxRateReconciliationPermanentTaxDifferencesAmount" id="imsr_IncomeTaxRateReconciliationPermanentTaxDifferencesAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="IncomeTaxRateReconciliationReturnToProvisionAdjustmentAmount" id="imsr_IncomeTaxRateReconciliationReturnToProvisionAdjustmentAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="IncomeTaxRateReconciliationChangesInForeignExchangeRateAmount" id="imsr_IncomeTaxRateReconciliationChangesInForeignExchangeRateAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="TerrestrialEnergyDevelopmentIncMember" id="imsr_TerrestrialEnergyDevelopmentIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="HcmIiAcquisitionCorpMember" id="imsr_HcmIiAcquisitionCorpMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LesseeOperatingLeaseMaximumExtensionTerm" id="imsr_LesseeOperatingLeaseMaximumExtensionTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="StockIssuedDuringPeriodValueMergerFinancing" id="imsr_StockIssuedDuringPeriodValueMergerFinancing" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="StockIssuedDuringPeriodSharesMergerFinancing" id="imsr_StockIssuedDuringPeriodSharesMergerFinancing" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ProceedsFromMergerFinancing" id="imsr_ProceedsFromMergerFinancing" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="NumberOfAdditionalSharesIssuedAndConvertedOfPreferredStock" id="imsr_NumberOfAdditionalSharesIssuedAndConvertedOfPreferredStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
</xsd:schema>
