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1.
Theoretical Study of the C_(60)O_3 Isomers   总被引:2,自引:0,他引:2  
WiththepreparationandisolationofC,,O.'moreandmoreattentionwaspaidtotheirstructuresandpropertiest').WooddetectedC,,O.firstwhentheypreparedC,,byvaporizinggraphite").Fromthenon,thelaboratoriesallovertheworldhavepreparedC6,O.byvariousmethodssuchasPhotoxidationt2-4),Electrochemicaloxi-dation[si,Ozonizationt7.83andChemicaladditiont6'12-14iandsoon.Accordingtothefollow-uptheoreticalstudiesforC,,O.,itisindicatedthattherearetwoisomersofC,,O:eithertheoxygenatomislocatedoverthe6/6bondtogeneratethe6/…  相似文献   

2.
1INTRODUCTIONThereactionsoftheundecatungstosilicate{SiW,,O,,j'-withmetalornon-metalionshavebeenextensivelyinvestigated"'-Sofar,mostofthesereactionsreportedintheliteraturehavebeenpreparedeither1nsolutionorunderthehydrothermaIcondi-tion.Recently,wehavepreparedMo(W)-Cu(Ag)-Sclustersbysolidstatereac-tionsatlowheatingtemperatures""'.Asanextensionofthisresearch,wereportherewiththesynthesisandcrystalstructureofH,[(n-llu),Nj,[As(SiW,,O,,)j.2EXPERIMENTALThetitlecompoundwasobtainedbyheat…  相似文献   

3.
1INTRODUCTIONBytreatingFeCo2(CO),(p,-S)withgroupVligands[L=PPh,,AsPh,,PBus",p(OEt),j,monosubstitutedderivativesFeCo2(CO),(p,-S)(L)havebeenobtained{1'2i.13C-NMRshowedthatthereplacementofCObyagroupVligandinFeCo,(CO),(p,-S)isatonecobaltatominthemonosubstitutedderivativet2).How-ever,thesubstitutedderivativeofFeCo,(CO),(p,-S)withP(OCH,Ph),hasnotbeenreportedanditscrystalstructurehasnotbeendetermined.WehavesynthesizedthetitlecompoundFeCo,(CO),(p,-S)[P(OCH,Ph),jandtestifiedth…  相似文献   

4.
1INTRoDUCTIONAmongthesilicates,rareearthdisilicatesarespecialbecausetheyshowexten-sivepolymorphism"~".Theconfigurationof(Si,O,)doubletetrahedraisrelativelyrelatedtoperiodicityoftherareearthelectronicstructures,suchasvariationinionicsizeordiscontinuityinchemicalbondingproperties,andalsousefulfordiscussingthedegreeofd-pffbondinginsilicates.SmolinandShepelevhavesynthesizedhightem-peratureformofNd,Si,O,crystallizedinorthorhombicsystem"'.Werecent1yob-tainedlowtemperatureformofNd,Si,O,,which…  相似文献   

5.
采用高温固相法合成了Ce3+,Tb3+掺杂激活的CaBa2(BO3)2荧光粉,并对其发光特性进行了研究。观察到CaBa2(BO3)2中Ce3+对Tb3+发光的敏化现象。在367 nm紫外光激发下,单掺Tb3+时CaBa2(BO3)2不发光。当Ce3+和Tb3+共掺时,出现Tb3+的发射峰,样品发绿光,表明Ce3+对Tb3+的发光有很强的敏化作用。根据Forster-Dexter理论,分析Ce3+和Tb3+的能量传递过程,还证明在CaBa2(BO3)2:Ce3+,Tb3+中Ce3+对Tb3+的能量传递属于共振能量传递。  相似文献   

6.
1INTRODUCTIONAlthoughseveralhundredpolyhedralmetallaboraneshavebeencharacterized,theincidenceofruthenaboranesisparticularlysurprising.(hThefirstpolyhedralruthenaboraneisstructurallytypifiedbythecompound[(PPh,)2RuB,,HS(OEt),j,whichisobtainedin40%yieldsfromthereactionbetweentRuCI,(PPh,),jandcloso-tB,,H,,j'--inCHCI,/EtOH.tZiWithCH,COOH/THFt'iandC,H,COOH/CH,CI,">insteadofCHCI,/EtOH,twocompoundsF{(PPh,)2Ru}~(p-MeCO,)3--(pH)z-{RuB,,H,}jand[(PPh,)2(PhCOO)RuB,,HSCljhav…  相似文献   

7.
TheheteropolytungstateisoneofthemostchallengingprojectsininorganicchemistryduetoitsaPPlicationonsolidstatechemistly,catalysis,biochemistry,separationandanalysis,etcl-4.Inthispaper,thepreparationmethodandluminescencepropertiesofEu' -dopedNanPZW22O83wereinvestigated.Therelationshipbetweentheluminescentpropertiesandcrystalstructurewasdiscussed.ExperimentalThesampleswerepreparedbysolidstatereactionfrommixturesofN'PZO7'10HZO,WOe,NaZWO"ZHzOandEuZO3.Thestoichiometricalmixtureswerecalcined…  相似文献   

8.
MThekeymaterials,5-amino-l,10-phenanthrolineandetS-Ru(phew,CI,,werepreparedbythemethodsofreferences"'.Synthesisofla,foandicEquimolaramountsofcorrespondingto-bromo-alkyIacyIohIondewasaddeddropwisetoasuspensionof5-amino-l,10-phenanthrolineandsodiumdicarbonateindryacetonitrilewithstirringatroomtemperatureundernitrogenfor4-6hours.Thentheresultingsolidwasfilteredandwashedbyacetonitrile,5%sodiumbicarbonateaqueoussolutionandwaterinturn.Afterbeingdriedicvacuo,yellowmicrocrystalsla-cwereobtained.Sy…  相似文献   

9.
以2-甲基苯甲酸(2-MBA)为第一配体、1,10-邻菲罗啉(phen)为第二配体,制备了三元铽配合物Tb(2-MBA)3phen和二元铽配合物Tb(2-MBA)3·2H2O,并利用元素分析、红外光谱、紫外光谱、荧光光谱和荧光寿命对二者的结构与性能进行分析表征。研究结果表明:三元铽配合物Tb(2-MBA)3phen的荧光发射强度要强于二元铽配合物Tb(2-MBA)3·2H2O,而二者的荧光寿命恰好相反,三元铽配合物Tb(2-MBA)3phen的荧光寿命短于二元铽配合物Tb(2-MBA)3·2H2O。热重分析表明Tb(2-MBA)3·2H2O的热分解温度要远高于Tb(2-MBA)3phen。  相似文献   

10.
1INTRODUCTIONHeteropolycompoundsareacidsaswellasoxidizingagents"'.Takingadvantageoftheseproperties,heteropolycompoundshavebeenusedascatalystsforvarioussyntheticreaction(bothinhomogeneousandheterogeneoussystems).Hydrationofpropeneinaliquidphasecatalyzedbyheteropolyacidshasbecomeacommercializedprocess.Oxidationofmethacroleinorisobutyricacidtoproducemethacrylicacidisanexampleofindustrialprocessestowhichthesecompoundsareapplied"--'>.Theoxidationpotential(oroxidizingability)decreaseslinearlywi…  相似文献   

11.
1INTRODUCT1oNMeta1liccomplexesofsomeSchiffbaseshaveantiviraIandfungistaticac-tivies[1-3i.SomeSchiffbasemetalliccomplexeshavecatalyticactivityasenzyme"'.Thisaspectacu1arresearchfield-WehavereportedthesynthesisandcrystalstructureofNd(llI)nitratecomplexwithN,N-disalicyclideneethylenediamineandDMSO(si'HerethetitlecomplexwasobtainedandcharacterizedbyX-raydiffrac-tion'Theligandisdischiffbaseofcondensationfrom2-hydroxyl-3-methoxyben-zoaldehydeandethylenediamine.2EXPERIMENTAL2.1Synthesi…  相似文献   

12.
Dithiolatemetalcomplexeshavegeneratedgreatinterestforalongtimeduetoitsuniqueelectronicandmagneticpropertieshave.Recently,anewsystemofdithiolateligands,combinedwiththeTTFmoiety,hasreceivedmuchattentionl.Underhilletal.havereportedonthestrUcturesofadianionicmercurycomplex[Nme412[Hg(C1oH1oS8)8],andlateronaplanarneutralnickelcomplex[Ni(C,,H,,S,),]"'.Strongdrr-pninteractionbetweenthecentralmetalionandtheconjugatedligands,andtherichredoxbehaviorsofthesecomplexesimplyagoodpotentialinitSapplicati…  相似文献   

13.
1INTRODUCTIONTheextractioncapacityofsulfur--containingsulfoxidesiscomparabletoandevengreaterthanthatoftributylphosphate(TBP)asanextractantfortheextractionandseparationofuraniumandthorium.Atthesametime,theradiolyticstabilityofsulfoxidesisbetterthanthatofTBP'1'23,SothesulfoxidecanbeusedpotentiallyforreprocessingofspentTh--Unuclearfuel.Howeverthecrystalstructureofuranylcomplexwithsulfoxideshas'notbeenreportedt3'4'93.Theknowledgeofthemolecularstructureofthetitlecomplexisusefulforinvestigat…  相似文献   

14.
Theeffectofethanol-watermixtureontheseconddissociationconstantofcarbonicacidwasofinterestnotonlyforbiologistsbutalsoforchefestsandchemicalengineers,becauseitmayprovideusefulinformationinregardtotheidentificationofthenatureofthesesolute-solventinteractionpatternsinbinarysolventsystem"'.ThispaperreportStheseconddissociationconstantsofcarbonicacid,K,,atfivetemperaturesfrom278.15to318.15Kin5,15,25mass%ethanol-water"dxedsolventsdeterminedfrompreciseelnfmeasurementsincell(A)withoutliquidjunction:Pt…  相似文献   

15.
1INTRODUCTIoNInthepastdecades,thechemistryofMo-Sclusterscontaininga[Mo,(p,-S)(p-S,),j corehasbeenstudiedtextensively,andmanysuchkindofcompoundshavebeensynthesized.(1'2'3'4iHowever,fewcompoundscontainingadiscreteclus-tercationhavebeenreported.[5iInthispaper,wereportthesynthesisandstructureofthetitlecompound.Thisisanewexampleoftrimolybdenumclustercontainingadiscreteclustercation.2EXPERIMENTALAllmanipulationwerecarriedoutinair.2.1Synthesis0f[M0,S,(S,P(iprO),),jtS,P(iprO),jAmixture…  相似文献   

16.
1INTRODUCT1ONThestudyofheteropolycomplexeshasbeenstartedmorethanonehundredyearsago.lnthepasttwentyyearstheheteropoly-coinplexesoftungstenandmolyb-denumhavebeenusedinpreparingcatalystfield,biologicalandionexchangemateri-als.Sothesecomplexeshavebeendeeplystudiedandexaminedbynewtechnicalmethodst2~7J.Wehavereportedthesynthesismethodandcrystalstructureoflanthanideele-mentneodymiumheteropolymolybdate(NH4),2H,,tNd'Mo,,O,,,(H,O)1,j.22H,O('i.Inthispaperwereportthesynthesismethodandcrystalstruc…  相似文献   

17.
1INTRODUCTIONFromreactionsof[RuCl,(PPh,),jwithcloso-[B,,H,,j'-respectivelyinEtOH/CH,Cl,t'i,CH,COOH/THF"'andC,H,COOH/CH,Cl,">solution,itcanbefoundthatbothalcoholandorganicacidcanreplacehydrogenatomsinborane.Further-more,accordingtotheirdifferentreactiontime(3h,1OOhand113hrespectively),wecanknowthatalcoholismoreactivetoreplacehydrogenatomsinborane.NowinordertoconfirmthisrulefurtherweusePhCH(OH)COOH/(CH3)2CHOHsolutioninsteadofabove-mentionedsolutions.Newcompounds(I)and(II…  相似文献   

18.
1INTRODUCTIONHeteroPOlymolybdatesareknownwithaverywiderangeofmetalionsithetypeandstabilityoftheclustersshowdependenceonboththeheteroatomandPH"'.TheknownheteroPOlymolybdateswhichincludemanganese(1)ormanganese(IV)havebeenreported.Afewofhetercrg-molybdateanionswiththemanganese(IIV)andnickel(IV)formsarecharacterizedandisostructural[2).Thesehigheroxidationstatespecieshavebeenpreparedpreviouslybyoxidationoflower--valentspecieswithPOwerfuloxidant,suchasPeroxydisulfateorPeroxymonosulfurica…  相似文献   

19.
林美娟  王文  章文贡 《应用化学》2004,21(12):1241-0
Eu(OPri)3/Tb(OPri)3共掺杂P(MMA-co-St);Eu(OPri)3/Tb(OPri)3;共掺杂;P(MMA-co-St);荧光性能  相似文献   

20.
Terbium p-chlorobenzoate complex with 1,10-phenanthroline, [Tb( p-ClBA)_3phen]_2 (1) has been obtained in the ethanol solution, where p-ClBA=p-chlorobenzoate and phen=1,10-phenanthroline. It crystallizes in the triclinic system, space group P1, a=1.008 1(2) nm, b=1.185 7(2) nm, c=1.431 1(3) nm, α=110.826(4)°, β=96.436(4)°, γ=101.737(4)°, Z=2. The two Tb(Ⅲ) ions are linked by four carboxylate groups through their bidentate bridging modes, forming a dimeric unit with crystallographic inversion center. Each terbium ion has an eight-coordinate geometry with four of the coordination sites occupied by four oxygen atoms from the four bridging carboxylates, respectively, two oxygen atoms from bidentate carboxylate, and the remaining positions occupied by two nitrogen atoms from a 1,10-phenanthroline molecule. The Tb(Ⅲ) ion adopt a distorted square antiprism coordination geometry. The excitation and luminescence data observed at room temperature show that the title complex emits very intensive green fluorescence under ultraviolet light. The result of thermal analysis indicates the complex [Tb(p-ClBA)_3phen]_2 is quite stable to heat. CCDC: 221921.  相似文献   

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