简介:ThereactionofsingletoxygenwithethylenehasbeenstudiedattheabinitiolevelwithbothHF/3-21GandHF/6-31Gbasissets,fullyoptimizingthegeometriesofthecriticalpoints.Thetransitionstateleadingtotheintermediateperoxiranefromtheinitialreactantsisfound,Iocatedat81.71kJ/molabovethedissociationlimit.Thevibrationalanalysisisdonewithtwobasissets.Fromtheresultsitcanbeseenthatthefrequencieshavenotbeenmadeanimprovementobviouslywithaugmented6-31Gcomparedto3-21Gbasis;itfollowsthatmainreasonfortoohighHF/3-21Gfrequencycouldmainlybethevibrationalanharmonicity.TheeigenvectorcorrespondingtothesingleimaginaryvibrationalfrequencyisdominatedbythelargerO-Odistance.Thefindingofthetransitionstateconfirmsthattheperoxiraneminimumcanbereachablepassingthroughaperoxirane-likesaddlepoint.Inaddition,themechanismsofthereactionformingoxiranearediscussedaswell.
简介:Sphere-likecompoundC8H17Si(OPhC12H25)3N(1)formsmesophases.Inordertoinvestigatetherelationshipbetweenmolecularstructureandliquidcrystalproperties,structuralstudiesarecarriedoutonthemodelmoleculesofcompound1anditssubstitutedderivativesusingahinitiocalculations.TheresultsshowthatthecyanoorchlorosubstitutedtribenzosilatranecompoundsR1Si(OPhR2)3N(R1R2=CNorCl)havemuchbiggerdipolemomentsoranisotropyofpolarizabilityandmorelikespherethanthecorrespondingalkylsubstitutedcompounds.Cyanoorchlorosubstitutedtribenzosilatraneswouldbebettercandidatesforsphere-likemeso-gens.
简介:基于密度,功能的理论(DFT)和投影机扩充了的精力充沛的计算挥动的Abinitio为决定lanthanidesesquioxidesLn_2O_3的多型性的方法(爪)(在哪儿行=稀土元素的元素,Y,和Sc),LnMO_3perovskites(在哪儿M=AlandGa),并且Ln_2B_2O_7pyrochlores(在哪儿B=Ti,Zr,和Hf)被报导。除了theC类型Ln_2O_3,相对latticest能力与立方的结构,计算全部的精力为是更加更否定的与非常估计的结果或试验性的结果同意了很好。随Ln~(3+)阳离子半径的增加,多态的结构显示出果汁饮料生产趋势。第三的氧化物陶艺的形成的热含量的趋势和数量从他们相当适合于的成分二进制代码氧化物综合了可得到的试验性的结果,和珍贵热力学的性质被负担得起到化合物,没有试验性的数据为是可得到的。两perovskitesandpyrochlores的形成的热含量趋于随Ln~(3+)阳离子半径的增加变得更否定。
简介:TheelectronicstructuresofCuS2,CuSe2andCuTe2withpyritestructures,withintheframeworkthedensity-functionaltheoryhavebeeninvestigated.ThecalculatedresultsexplainedtherecentexperimentalresultswhichshowthatthereisnoclearindicationofstrongelectroncorrelationsintheelectronicpropertiesofCupyrites,duetothedominantchalcogenpcharacterratherthandcharacteristicofCuattheFermilevel.
简介:Thispapercarriesoutabinitiocalculationstostudythe80Se2(X3Σg-)stateand80Se2(X2Πg),80Se2(a4Πg)statesbyusingcompletedactivespaceself-consistentfieldandmulti-referencesecondorderperturbationtheory.Theelectroniccurvesofthesestatesincludingspin-orbitcouplingarecalculated,andthenthespectroscopicparametersareobtained.Thephotoelectronspectraof80Se2moleculeingasphaseareassignedaccordingtoFranck-Condonanalysisbasedoncalculatedpotentialenergycurves.Theionizationenergiesof80Se2moleculearedeterminedbythepresentcalculation.
简介:Theabinitiogeneralizedgradientapproximation(GGA)+Ustudyofmultiferroic(La0.5Bi0.5)2FeCrO6inpnmastructureandferri-magneticorder,includingHubbardcorrections(U-4.1eV)fortransitionmetal/rareearthd-electronswith20atomscell,showsoptimumlocalmagneticmomentsof(Cr^3+,Fe^3+)equalto(-2.56,4.14)#Bandanidealspin-downbandgapof1.54eV.Tuned-bandgapLa-substituteddoubleoxideperovskitesBFCOshouldexhibitenhancedvisible-lightabsorptionandcarriermobility,thuscouldbeconvenientlightabsorbersandthenefficientalternativestowide-gapchalcopyriteabsorber-basedsolarcellsfailingtoachievehighestpowerconversionefficiencies,andevencompetewiththeirmetal-organichalideperovskitescounterparts.
简介:AbinitiomolecularorbitalcalculationsofdoublynegativechargedB16H162-(D2)andneutralB16H16(Td)havebeendoneattheHF/6-31Glevel.TheyarepredictedtobechemicallyandkineticallystablebyvibrationalanalysesontheirrespectiveenergyhypersurfaceoftheHF/6-31Glevel.ThegeometricalstructureofthespeciesB16H1622-(D2)wasdiscussed.