密度泛函理论研究过渡金属掺杂的氧化镁(mgo)n(2≤n≤12)团簇结构与性质

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1、北京化工人学fi!；{i：学位论文10west—ene略yMnMgn．1On(n=2_lO)structures．ThestabilityanalysisclearlyrepresentsthattheaVeragebindingenergiesofthedopedclustersarela玛erthanthatofthecorrespondingpure(MgO)nclusters．MaximumpeaksofthesecondorderenergydifjferencesareobseⅣedforMnMgn—lOnclustersatn=6，

2、9，inlplyingthattheseclustersexhibithigherstabilitythantheirneighboringclusters．ByinVestigatingtheHOMO—LUMOgapsofthelowest—ene硌yMn—dopedmagnesiaclusters，itisfoundthatMnM9203，MnM9506，andMnM9809exhibithighchemicalinactiVe．Inaddition，a11theMn—dopedmagnesiaclustersexhibithightotal

3、magneticmomentswiththeexceptionofMnM902whichhas3．OO“B．TheirmagneticbehaViorisattributedtotheimpurityMnatom，thechargetransfermodes，andtheclustersizeofMnMgn．1Onclusters．2．C0adso印tiononTM—dopedmagnesiananotubes(TM=Ni，PdandPt)havebeenstudied．Firstly；wecalculatedthestructuralprope

4、rtiesandstabilitiesofNi，Pd，Ptdoped(M90)12nanotubes．Theresultsshowthattheinitialnanotubeslightlydef-onllsundertheinducingoftheseimpurityatoms，buttheirstabilitiesalmosthavenotchanged．ThecalculationresultsofCOadso印tiononTM—dopedmagnesiananotubesdemonstratethatCOfaVoursadsoptiono

5、nTM—dopedmagnesiananotubesintheformofCatombondingwithTMatom．FukuiindicesanalysisclearlyexhibitsthatdopingofimpurityTMatomallowsforanoticeablyenhancementofnucleophilicreactiVityabilityofmagnesiananotube．Theadsoq)tionenergiesdemonstratethatCOABSTRACTm01eculeismorestron91yboundo

6、nthe3一f01dTMatomsthanthe4一foldTMatoms．ThisfindingiswellconfimedbyTM—Cbondlength，cha玛etransferandC—Ovibrationalfrequency．Thehighads01ptionenergyof2．55eVisf．oundwhenC0adsorbson3一f01dPtinPt—dopedmagnesiananotubes，implyingthekindofthedopingTMatomhasasignificantinfluenceonthechemi

7、calreactiVity．3．Theadso印tionofS02onpureandCu，Auatomsdoped(M90)12nanotubesweresystematicallystudied．Firstly，thestmcturalpropertiesandstabilitiesofCu，Auatomsdoped(M90)12nanotubeshaVebeencalculated．ThegeometWoptimizationshowsthatthekindofimpurityatomandthedif诧rentofsubstitutesit

8、ehaVeagreatef-fectonthedopedcon69uration．TheaVeragebindingene唱yresul