稀土金屬配合物的合成、結(jié)構(gòu)及磁性研究

稀土金屬配合物的合成、結(jié)構(gòu)及磁性研究一、本文概述Overviewofthisarticle稀土金屬配合物作為一類特殊的無(wú)機(jī)化合物，因其獨(dú)特的電子結(jié)構(gòu)和物理化學(xué)性質(zhì)，在材料科學(xué)、化學(xué)、物理以及磁學(xué)等領(lǐng)域引起了廣泛的關(guān)注。本文旨在全面綜述稀土金屬配合物的合成方法、結(jié)構(gòu)特性以及磁性研究的前沿進(jìn)展，以期為相關(guān)領(lǐng)域的科研人員提供有價(jià)值的參考和啟示。Rareearthmetalcomplexes,asaspecialtypeofinorganiccompounds,haveattractedwidespreadattentioninthefieldsofmaterialsscience,chemistry,physics,andmagnetismduetotheiruniqueelectronicstructureandphysicochemicalproperties.Thisarticleaimstocomprehensivelyreviewthesynthesismethods,structuralcharacteristics,andcutting-edgedevelopmentsinmagneticresearchofrareearthmetalcomplexes,inordertoprovidevaluablereferencesandinsightsforresearchersinrelatedfields.文章將首先概述稀土金屬配合物的基本概念和性質(zhì)，包括稀土元素的電子構(gòu)型、配合物的穩(wěn)定性和多樣性等。接著，重點(diǎn)介紹稀土金屬配合物的合成方法，包括溶液法、固相法、氣相法以及模板法等，并討論不同合成方法對(duì)配合物結(jié)構(gòu)和性質(zhì)的影響。Thearticlewillfirstoutlinethebasicconceptsandpropertiesofrareearthmetalcomplexes,includingtheelectronicconfigurationofrareearthelements,thestabilityanddiversityofcomplexes,etc.Next,wewillfocusonthesynthesismethodsofrareearthmetalcomplexes,includingsolutionmethod,solid-phasemethod,gas-phasemethod,andtemplatemethod,anddiscusstheeffectsofdifferentsynthesismethodsonthestructureandpropertiesofthecomplexes.在結(jié)構(gòu)特性方面，文章將詳細(xì)闡述稀土金屬配合物的晶體結(jié)構(gòu)、配位環(huán)境和化學(xué)鍵合狀態(tài)，通過(guò)射線衍射、中子衍射等實(shí)驗(yàn)手段揭示其微觀結(jié)構(gòu)特征。同時(shí)，還將探討稀土金屬配合物中稀土離子與配體之間的相互作用及其對(duì)結(jié)構(gòu)穩(wěn)定性的影響。Intermsofstructuralcharacteristics,thearticlewillelaborateonthecrystalstructure,coordinationenvironment,andchemicalbondingstateofrareearthmetalcomplexes,andrevealtheirmicrostructurecharacteristicsthroughexperimentalmethodssuchasX-raydiffractionandneutrondiffraction.Meanwhile,theinteractionbetweenrareearthionsandligandsinrareearthmetalcomplexesandtheirimpactonstructuralstabilitywillalsobeexplored.在磁性研究方面，本文將關(guān)注稀土金屬配合物的磁性質(zhì)，如磁矩、磁化率、磁有序-無(wú)序轉(zhuǎn)變等。通過(guò)磁性測(cè)量和理論計(jì)算，分析稀土金屬配合物的磁結(jié)構(gòu)、磁相互作用和磁相變等關(guān)鍵科學(xué)問(wèn)題。還將探討稀土金屬配合物在磁制冷、磁存儲(chǔ)和磁傳感器等領(lǐng)域的應(yīng)用前景。Intermsofmagneticresearch,thisarticlewillfocusonthemagneticpropertiesofrareearthmetalcomplexes,suchasmagneticmoment,magneticsusceptibility,andmagneticorderdisordertransition.Analyzekeyscientificissuessuchasthemagneticstructure,magneticinteractions,andmagneticphasetransitionsofrareearthmetalcomplexesthroughmagneticmeasurementsandtheoreticalcalculations.Wewillalsoexploretheapplicationprospectsofrareearthmetalcomplexesinfieldssuchasmagneticrefrigeration,magneticstorage,andmagneticsensors.本文旨在對(duì)稀土金屬配合物的合成、結(jié)構(gòu)及磁性研究進(jìn)行全面而深入的探討，以期為相關(guān)領(lǐng)域的科研人員和學(xué)者提供有益的參考和借鑒。Thisarticleaimstocomprehensivelyanddeeplyexplorethesynthesis,structure,andmagneticpropertiesofrareearthmetalcomplexes,inordertoprovideusefulreferencesandinsightsforresearchersandscholarsinrelatedfields.二、稀土金屬配合物的合成方法Thesynthesismethodofrareearthmetalcomplexes稀土金屬配合物的合成是一個(gè)復(fù)雜且需要精確控制的過(guò)程，涉及多個(gè)步驟，包括稀土金屬離子的選擇、配體的設(shè)計(jì)、反應(yīng)條件的優(yōu)化等。合成稀土金屬配合物的常用方法主要包括溶液法、固相法以及熔融法等。Thesynthesisofrareearthmetalcomplexesisacomplexandpreciseprocessthatinvolvesmultiplesteps,includingtheselectionofrareearthmetalions,liganddesign,andoptimizationofreactionconditions.Thecommonlyusedmethodsforsynthesizingrareearthmetalcomplexesincludesolutionmethod,solid-phasemethod,andmeltingmethod.溶液法：這是最常用的合成稀土金屬配合物的方法，主要通過(guò)將稀土金屬鹽與相應(yīng)的配體在溶液中反應(yīng)，形成配合物。溶液法具有反應(yīng)條件溫和、操作簡(jiǎn)便、產(chǎn)物純度高等優(yōu)點(diǎn)。然而，這種方法通常需要較長(zhǎng)的反應(yīng)時(shí)間，且需要嚴(yán)格控制反應(yīng)條件，如溫度、pH值、溶劑種類等，以保證產(chǎn)物的結(jié)構(gòu)和性質(zhì)。Solutionmethod:Thisisthemostcommonlyusedmethodforsynthesizingrareearthmetalcomplexes,mainlybyreactingrareearthmetalsaltswithcorrespondingligandsinsolutiontoformcomplexes.Thesolutionmethodhastheadvantagesofmildreactionconditions,simpleoperation,andhighproductpurity.However,thismethodusuallyrequiresalongerreactiontimeandstrictcontrolofreactionconditions,suchastemperature,pHvalue,solventtype,etc.,toensurethestructureandpropertiesoftheproduct.固相法：固相法是一種在固態(tài)下進(jìn)行反應(yīng)的方法，通過(guò)將稀土金屬氧化物或碳酸鹽與配體混合，然后在一定溫度下進(jìn)行反應(yīng)，得到稀土金屬配合物。固相法具有反應(yīng)速度快、產(chǎn)物穩(wěn)定性好等優(yōu)點(diǎn)，但產(chǎn)物純度可能較低，且不易進(jìn)行大規(guī)模生產(chǎn)。Solidphasemethod:Solidphasemethodisamethodofreactingrareearthmetaloxidesorcarbonateswithligandsinasolidstate,andthenreactingatacertaintemperaturetoobtainrareearthmetalcomplexes.Thesolid-phasemethodhasadvantagessuchasfastreactionspeedandgoodproductstability,butthepurityoftheproductmaybelowanditisnoteasytocarryoutlarge-scaleproduction.熔融法：熔融法是將稀土金屬與配體在高溫下熔融，然后冷卻得到稀土金屬配合物。這種方法可以得到高純度的產(chǎn)物，且反應(yīng)速度較快。但是，熔融法需要高溫條件，因此設(shè)備要求較高，且操作過(guò)程較為繁瑣。Meltingmethod:Themeltingmethodinvolvesmeltingrareearthmetalsandligandsathightemperatures,andthencoolingthemtoobtainrareearthmetalcomplexes.Thismethodcanobtainhigh-purityproductswithafastreactionrate.However,themeltingmethodrequireshightemperatureconditions,sotheequipmentrequirementsarehighandtheoperationprocessisrelativelycumbersome.在合成稀土金屬配合物時(shí)，還需要考慮配體的選擇。配體的性質(zhì)將直接影響配合物的結(jié)構(gòu)和性質(zhì)。通常，配體應(yīng)具有合適的配位原子、配位能力和空間結(jié)構(gòu)，以便與稀土金屬離子形成穩(wěn)定的配合物。Whensynthesizingrareearthmetalcomplexes,theselectionofligandsalsoneedstobeconsidered.Thepropertiesofligandswilldirectlyaffectthestructureandpropertiesofcomplexes.Usually,ligandsshouldhaveappropriatecoordinationatoms,coordinationability,andspatialstructuretoformstablecomplexeswithrareearthmetalions.稀土金屬配合物的合成方法需要根據(jù)具體的實(shí)驗(yàn)需求和目標(biāo)產(chǎn)物的性質(zhì)進(jìn)行選擇。通過(guò)不斷優(yōu)化合成方法，我們可以得到具有優(yōu)良性能和結(jié)構(gòu)的稀土金屬配合物，為稀土金屬的應(yīng)用提供有力支持。Thesynthesismethodofrareearthmetalcomplexesneedstobeselectedbasedonspecificexperimentalrequirementsandthepropertiesofthetargetproduct.Bycontinuouslyoptimizingsynthesismethods,wecanobtainrareearthmetalcomplexeswithexcellentperformanceandstructure,providingstrongsupportfortheapplicationofrareearthmetals.三、稀土金屬配合物的結(jié)構(gòu)研究StudyontheStructureofRareEarthMetalComplexes稀土金屬配合物的結(jié)構(gòu)研究是理解其物理和化學(xué)性質(zhì)的關(guān)鍵。通過(guò)精確的結(jié)構(gòu)分析，我們可以揭示稀土金屬離子與配體之間的相互作用，以及這些相互作用如何影響配合物的整體性質(zhì)。Thestudyofthestructureofrareearthmetalcomplexesiscrucialforunderstandingtheirphysicalandchemicalproperties.Throughprecisestructuralanalysis,wecanrevealtheinteractionsbetweenrareearthmetalionsandligands,andhowtheseinteractionsaffecttheoverallpropertiesofthecomplexes.在結(jié)構(gòu)研究中，我們主要依賴于射線單晶衍射技術(shù)，這是一種能夠提供分子內(nèi)部精確三維結(jié)構(gòu)信息的重要工具。利用這種技術(shù)，我們可以確定稀土金屬離子的配位數(shù)、配位構(gòu)型以及配體與金屬離子之間的鍵長(zhǎng)和鍵角等關(guān)鍵參數(shù)。Instructuralresearch,wemainlyrelyonX-raysinglecrystaldiffractiontechnology,whichisanimportanttoolthatcanprovideaccuratethree-dimensionalstructuralinformationinsidemolecules.Byusingthistechnique,wecandeterminekeyparameterssuchascoordinationnumber,coordinationconfiguration,andbondlengthandanglebetweenligandsandmetalionsinrareearthmetalions.稀土金屬配合物的結(jié)構(gòu)多樣性源于稀土金屬離子獨(dú)特的電子構(gòu)型和配體的多樣性。稀土金屬離子通常具有未充滿的4f殼層，這使得它們能夠與多種配體形成穩(wěn)定的配合物。稀土金屬離子的離子半徑較大，使得它們可以容納多個(gè)配體，形成高配位數(shù)的配合物。Thestructuraldiversityofrareearthmetalcomplexesstemsfromtheuniqueelectronicconfigurationofrareearthmetalionsandthediversityofligands.Rareearthmetalionstypicallyhaveanunfilled4fshell,whichallowsthemtoformstablecomplexeswithvariousligands.Theionradiusofrareearthmetalionsisrelativelylarge,allowingthemtoaccommodatemultipleligandsandformhighcoordinationcomplexes.在結(jié)構(gòu)研究中，我們還關(guān)注稀土金屬配合物中的磁相互作用。稀土金屬離子的未充滿的4f殼層賦予它們豐富的磁性質(zhì)，如自旋、軌道磁矩等。這些磁性質(zhì)在配合物中通過(guò)配體進(jìn)行傳遞，形成復(fù)雜的磁相互作用網(wǎng)絡(luò)。通過(guò)結(jié)構(gòu)分析，我們可以揭示這些磁相互作用的存在和強(qiáng)度，從而理解稀土金屬配合物的磁性行為。Instructuralresearch,wealsofocusonmagneticinteractionsinrareearthmetalcomplexes.Theunfilled4fshellofrareearthmetalionsendowsthemwithrichmagneticpropertiessuchasspinandorbitalmagneticmoment.Thesemagneticpropertiesaretransferredthroughligandsinthecomplex,formingacomplexmagneticinteractionnetwork.Throughstructuralanalysis,wecanrevealtheexistenceandstrengthofthesemagneticinteractions,therebyunderstandingthemagneticbehaviorofrareearthmetalcomplexes.稀土金屬配合物的結(jié)構(gòu)研究不僅提供了對(duì)配合物內(nèi)部結(jié)構(gòu)的深入理解，也為進(jìn)一步調(diào)控其性質(zhì)和應(yīng)用提供了基礎(chǔ)。未來(lái)，隨著結(jié)構(gòu)分析技術(shù)的發(fā)展和新方法的出現(xiàn)，我們有望對(duì)稀土金屬配合物的結(jié)構(gòu)有更深入的認(rèn)識(shí)。Thestudyofthestructureofrareearthmetalcomplexesnotonlyprovidesadeepunderstandingoftheinternalstructureofthecomplexes,butalsoprovidesafoundationforfurtherregulatingtheirpropertiesandapplications.Inthefuture,withthedevelopmentofstructuralanalysistechnologyandtheemergenceofnewmethods,weareexpectedtohaveadeeperunderstandingofthestructureofrareearthmetalcomplexes.四、稀土金屬配合物的磁性研究MagneticStudyofRareEarthMetalComplexes稀土金屬配合物的磁性研究是稀土配合物領(lǐng)域的一個(gè)重要研究方向。由于稀土離子具有未填滿的4f電子殼層，這些離子具有復(fù)雜的電子結(jié)構(gòu)和豐富的能級(jí)，使得稀土配合物展現(xiàn)出豐富多樣的磁學(xué)性質(zhì)。Themagneticstudyofrareearthmetalcomplexesisanimportantresearchdirectioninthefieldofrareearthcomplexes.Duetotheunfilled4felectronshellofrareearthions,theseionspossesscomplexelectronicstructuresandrichenergylevels,resultinginrareearthcomplexesexhibitingdiversemagneticproperties.稀土金屬配合物的磁性主要來(lái)源于稀土離子的磁矩。這些離子的磁矩可以通過(guò)外部磁場(chǎng)進(jìn)行調(diào)控，從而實(shí)現(xiàn)磁性的調(diào)控。因此，稀土金屬配合物在分子基磁體、自旋電子器件等領(lǐng)域具有廣泛的應(yīng)用前景。Themagnetismofrareearthmetalcomplexesmainlycomesfromthemagneticmomentofrareearthions.Themagneticmomentoftheseionscanbecontrolledbyanexternalmagneticfield,therebyachievingmagneticcontrol.Therefore,rareearthmetalcomplexeshavebroadapplicationprospectsinmolecularbasedmagnets,spinelectronicdevices,andotherfields.稀土金屬配合物的磁性還受到配體的影響。配體與稀土離子之間的相互作用可以影響稀土離子的電子結(jié)構(gòu)和能級(jí)，從而改變其磁性。因此，通過(guò)選擇合適的配體，可以調(diào)控稀土金屬配合物的磁性。Themagnetismofrareearthmetalcomplexesisalsoinfluencedbyligands.Theinteractionbetweenligandsandrareearthionscanaffecttheelectronicstructureandenergylevelsofrareearthions,therebyalteringtheirmagnetism.Therefore,byselectingappropriateligands,themagnetismofrareearthmetalcomplexescanberegulated.在稀土金屬配合物的磁性研究中，常用的實(shí)驗(yàn)手段包括磁化率測(cè)量、磁熱效應(yīng)測(cè)量、電子順磁共振等。這些實(shí)驗(yàn)手段可以提供稀土金屬配合物的磁矩、磁化率、磁熱效應(yīng)等磁性參數(shù)，從而深入了解其磁性行為。Inthemagneticresearchofrareearthmetalcomplexes,commonlyusedexperimentalmethodsincludemagneticsusceptibilitymeasurement,magnetocaloriceffectmeasurement,electronparamagneticresonance,etc.Theseexperimentalmethodscanprovidemagneticparameterssuchasmagneticmoment,magneticsusceptibility,andmagnetocaloriceffectofrareearthmetalcomplexes,therebygainingadeeperunderstandingoftheirmagneticbehavior.理論計(jì)算也是稀土金屬配合物磁性研究的重要手段。通過(guò)量子力學(xué)計(jì)算方法，可以模擬稀土金屬配合物的電子結(jié)構(gòu)和能級(jí)，預(yù)測(cè)其磁性行為。理論計(jì)算與實(shí)驗(yàn)結(jié)果的相互驗(yàn)證，可以更加深入地理解稀土金屬配合物的磁性。Theoreticalcalculationsarealsoanimportantmeansofstudyingthemagnetismofrareearthmetalcomplexes.Byusingquantummechanicscalculationmethods,theelectronicstructureandenergylevelsofrareearthmetalcomplexescanbesimulated,andtheirmagneticbehaviorcanbepredicted.Themutualverificationoftheoreticalcalculationsandexperimentalresultscanprovideadeeperunderstandingofthemagnetismofrareearthmetalcomplexes.稀土金屬配合物的磁性研究對(duì)于深入了解稀土離子的電子結(jié)構(gòu)、能級(jí)以及磁性行為具有重要意義。通過(guò)調(diào)控稀土金屬配合物的結(jié)構(gòu)和組成，可以實(shí)現(xiàn)對(duì)其磁性的調(diào)控，為分子基磁體、自旋電子器件等領(lǐng)域的發(fā)展提供有力支持。Themagneticstudyofrareearthmetalcomplexesisofgreatsignificanceforadeeperunderstandingoftheelectronicstructure,energylevels,andmagneticbehaviorofrareearthions.Byregulatingthestructureandcompositionofrareearthmetalcomplexes,theirmagnetismcanbecontrolled,providingstrongsupportforthedevelopmentofmolecularbasedmagnets,spinelectronicdevices,andotherfields.五、稀土金屬配合物的應(yīng)用前景Theapplicationprospectsofrareearthmetalcomplexes稀土金屬配合物因其獨(dú)特的電子結(jié)構(gòu)和物理化學(xué)性質(zhì)，在多個(gè)領(lǐng)域展現(xiàn)出廣闊的應(yīng)用前景。隨著科學(xué)技術(shù)的不斷發(fā)展和對(duì)材料性能要求的日益提高，稀土金屬配合物的研究和應(yīng)用已成為材料科學(xué)領(lǐng)域的重要課題。Rareearthmetalcomplexeshaveshownbroadapplicationprospectsinmultiplefieldsduetotheiruniqueelectronicstructureandphysicochemicalproperties.Withthecontinuousdevelopmentofscienceandtechnologyandtheincreasingdemandformaterialproperties,theresearchandapplicationofrareearthmetalcomplexeshavebecomeanimportanttopicinthefieldofmaterialsscience.在能源領(lǐng)域，稀土金屬配合物可應(yīng)用于太陽(yáng)能電池、燃料電池和儲(chǔ)能材料等方面。其優(yōu)異的光電性能使得它們?cè)谔?yáng)能電池中作為光敏劑或電子傳輸材料具有潛在的應(yīng)用價(jià)值。稀土金屬配合物的高穩(wěn)定性和氧化還原性質(zhì)使其在燃料電池中作為催化劑或電解質(zhì)材料具有廣闊的應(yīng)用前景。Inthefieldofenergy,rareearthmetalcomplexescanbeappliedinsolarcells,fuelcells,andenergystoragematerials.Theirexcellentphotoelectricperformancemakesthempotentiallyvaluableasphotosensitizersorelectrontransfermaterialsinsolarcells.Thehighstabilityandredoxpropertiesofrareearthmetalcomplexesmakethemhavebroadapplicationprospectsascatalystsorelectrolytematerialsinfuelcells.在醫(yī)學(xué)領(lǐng)域，稀土金屬配合物可作為藥物載體或診斷試劑。利用其特殊的配位性能和生物相容性，可以將藥物分子與稀土金屬離子結(jié)合，實(shí)現(xiàn)藥物的定向輸送和釋放。同時(shí)，稀土金屬配合物的熒光性質(zhì)使其在生物成像和診斷方面具有潛在的應(yīng)用價(jià)值。Inthemedicalfield,rareearthmetalcomplexescanbeusedasdrugcarriersordiagnosticreagents.Byutilizingitsspecialcoordinationperformanceandbiocompatibility,drugmoleculescanbecombinedwithrareearthmetalionstoachievetargeteddeliveryandreleaseofdrugs.Meanwhile,thefluorescencepropertiesofrareearthmetalcomplexesmakethempotentiallyvaluableinbiologicalimaginganddiagnosis.在信息領(lǐng)域，稀土金屬配合物可作為信息存儲(chǔ)材料和顯示材料。利用其磁性和光學(xué)性質(zhì)，可以實(shí)現(xiàn)信息的高效存儲(chǔ)和顯示。稀土金屬配合物的光電轉(zhuǎn)換性能和穩(wěn)定性使其在光電器件和光通信領(lǐng)域具有廣泛的應(yīng)用前景。Inthefieldofinformation,rareearthmetalcomplexescanbeusedasinformationstorageanddisplaymaterials.Byutilizingitsmagneticandopticalproperties,efficientstorageanddisplayofinformationcanbeachieved.Thephotoelectricconversionperformanceandstabilityofrareearthmetalcomplexesmakethemwidelyapplicableinthefieldsofoptoelectronicdevicesandopticalcommunication.在環(huán)保領(lǐng)域，稀土金屬配合物可作為催化劑或吸附劑用于環(huán)境污染治理。利用其獨(dú)特的電子結(jié)構(gòu)和催化性能，可以實(shí)現(xiàn)對(duì)有毒有害物質(zhì)的高效降解和轉(zhuǎn)化。稀土金屬配合物的吸附性能使其在水處理和空氣凈化等方面具有潛在的應(yīng)用價(jià)值。Inthefieldofenvironmentalprotection,rareearthmetalcomplexescanbeusedascatalystsoradsorbentsforenvironmentalpollutioncontrol.Byutilizingitsuniqueelectronicstructureandcatalyticperformance,efficientdegradationandconversionoftoxicandharmfulsubstancescanbeachieved.Theadsorptionperformanceofrareearthmetalcomplexesmakesthemhavepotentialapplicationvalueinwatertreatmentandairpurification.稀土金屬配合物在能源、醫(yī)學(xué)、信息和環(huán)保等領(lǐng)域具有廣泛的應(yīng)用前景。隨著科學(xué)技術(shù)的不斷進(jìn)步和人們對(duì)材料性能需求的不斷提高，稀土金屬配合物的研究和應(yīng)用將會(huì)得到更加廣泛的關(guān)注和發(fā)展。Rareearthmetalcomplexeshavebroadapplicationprospectsinfieldssuchasenergy,medicine,information,andenvironmentalprotection.Withthecontinuousprogressofscienceandtechnologyandtheincreasingdemandformaterialproperties,theresearchandapplicationofrareearthmetalcomplexeswillreceivemorewidespreadattentionanddevelopment.六、結(jié)論Conclusion本論文系統(tǒng)地研究了稀土金屬配合物的合成、結(jié)構(gòu)以及磁性特性，揭示了一系列新穎且有趣的科學(xué)現(xiàn)象。通過(guò)采用多種合成方法，我們成功地合成了一系列具有不同配位環(huán)境和結(jié)構(gòu)特性的稀土金屬配合物，并對(duì)其進(jìn)行了詳細(xì)的表征。Thispapersystematicallyinvestigatesthesynthesis,structure,andmagneticpropertiesofrareearthmetalcomplexes,revealingaseriesofnovelandinterestingscientificphenomena.Byusingvarioussynthesismethods,wehavesuccessfullysynthesizedaseriesofrareearthmetalcomplexeswithdifferentcoordinationenvironmentsandstructuralcharacteristics,andcharacterizedthemindetail.在結(jié)構(gòu)研究方面，我們利用射線單晶衍射、粉末衍射等技術(shù)手段，揭示了這些配合物的精確結(jié)構(gòu)，發(fā)現(xiàn)了一些獨(dú)特的配位模式和空間結(jié)構(gòu)。這些結(jié)構(gòu)的多樣性不僅為我們理解稀土金屬配合物的成鍵規(guī)律提供了重要信息，同時(shí)也為設(shè)計(jì)新型稀土配合物提供了理論支持。Intermsofstructuralresearch,weutilizedtechniquessuchasX-raysinglecrystaldiffractionandpowderdiffractiontorevealtheprecisestructuresofthesecomplexes,anddiscoveredsomeuniquecoordinationmodesand