A New Synthetic Route to Di-η~5-Cyclopentadienyl Ytterbium(Ⅱ)Tetrafuranate (η~5-C_5H_5)_2Yb(THF)_2 and Its Crystal Structure

In recent years,the organometallic ehemistry of the lanthanide metals in low oxidation states has beenactively investigated.The synthesis of the low一valent lanthanide eomPlexes has the signifieant meanings ontheory and praeti     

RE_(0.06)La_(0.94)Nb_2O_6Cl的制备与光谱性质(RE=Pr、Eu、Tb、Dy)

本文采用真空下气体输运技术制备RE_(0.06)La_(0.94)Nb_2O_6Cl(RE=Pr、Eu、Tb、Dy)小单晶和多晶粉末样品。测定其晶体结构与LaNb_2O_6Cl的晶体结构相同,为正交晶系;Eu_(0.06)La_(0.94)Nb_2O_6Cl小单晶的晶胞参数为:a=9.751,b=7.321,c=8.364。观察RE_(0.06)La_(0.94)Nb_2O_6Cl(RE=Pr、Eu、Tb、Dy)的特征激发光谱和发射光谱及其能量传递现象。     

Crystal Structure of{[(μ_2-Cl)(C_5H_5)Sm(μ_2-Cl)]_2(μ_3-Cl)(μ_4-O)Sm(μ_2-Cl)·THF}_2~(2-)·[Li(DME)_2·Li(THF)_2·DME]~(2 )·DME

The crystal structure of title complex has been determined by the method of X-ray single crystaldiffraction.The crystal belongs to monoclinic space group C_(2/c)with the unit parameters a=2.8907(7),b=2.0431(5),c=1.5723(3)nm;β=115.67(2)°.The unit volume V is 8.36924(348)nm~3;Z=8,Dc=1,82g·cm~(-3),μ(MoK_α)=46.4cn~(-1); F(000)=4416.The final R is 0.083,Rw 0.088.The title complex con-sists of two univalent cations and one divalent anion.The anion has a cluster structure including six Sm~(3 ).Coordination numbers of all six Sm~(3 )are eight,but their surroundings are different from each other.Two ofthem are decahedral array,and the others are octahedral array f the centroid of each pentacyclodienyl ring istaken as one point.