镨、钕、钇、甘氨酸三元配合物的晶体结构

在水溶液中培养了镨、钕、钇与甘氨酸形成的三元配合物。元素分析和热分析表明，该配合物可用Ｐｒ_ｘＮｄ_ｙＹ_ｚ（Ｇｌｙ）_６（Ｈ_２Ｏ）_４（ＣｌＯ_４）_６·５Ｈ_２Ｏ（Ｘ＋ｙ＋ｚ＝２）表示其分子式。Ｘ射线衍射方法测定了其单晶结构，结果表明，该晶体属三斜晶系，空间群Ｐ１，化学式Ｐｒ_（０．７７５）Ｎｄ_（０．７００）Ｙ_（０．５２５）Ｃｌ_６Ｏ_（４５）Ｎ_６Ｃ_（１２）Ｈ_（４８），Ｍ_ｒ＝１４６６．０９，晶胞参数如下：ａ＝１１．５６４（１），ｂ＝１４．１１８（３），ｃ＝１５．６６８（２）Ａ，α＝９６．９９（１），β＝１０２．７２（１），γ＝１０５．３３（１）°，晶胞体积Ｖ＝２３６２（１）Ａ~３，Ｚ＝２，Ｄ_ｃ＝２．０６０ｇ／ｃｍ~３，结构偏离因子Ｒ＝０．０３２，Ｒ_ｗ＝０．０４８。晶胞中存在两个络合单元，每个单元可用Ｍ_１Ｍ２（Ｇｌｙ）_６（ＣｌＯ_４）_６（Ｈ_２Ｏ）_４．５Ｈ_２Ｏ表示，Ｍ_１＝０．４Ｐｒ＋０．３７５Ｎｄ＋０．２２５Ｙ，Ｍ２＝０．３７５Ｐｒ＋０．３２５Ｎｄ＋０．３０Ｙ。三种稀土元素按一定比例统计性地占有两个格位。羧基以桥式联结金属离子，形成一维链式聚合物结构。在络合单元中，一个稀土离子是９配位，其配位多面体为畸变?

Synthesis,Characterization and Crystal Structure of a Heternuclear Mixed Complex of Praseodymium,Neodymium and Yttrium with Glycinic Acid

The heternuclear mixed complex Pr_x Nd_yY_z(Gly)_6(ClO_4)_6(H_2O) 4·SH_2O(x+ y+z =2) has been synthesized in the aqueous solution.The X-ray single crystal structure analysis shows that the crystal is triclinic system with space group P1 and the unit cell parameters are as follows:a=11.564(1),b=14.118(3),c=15.668(2) A,α=96.99(1)°,β=102.72(1)°,γ=105.33 (1)°.There are two complex units in the unit cell,every complex unit is M_1M_2 (Gly)_6(ClO_4)_6-( H_2O)_4·5H_2O, M_1=0.495Pr + 0.375Nd + 0.225Y,M_2 =0.375Pr+ 0.325Nd + 0.30Y.Three rare earth ions each occupy the two positions statistically with the definite proportions.The crystal is a one-dimenstional chain structure the carboxyl of glycinic acid serves as bridging groups connecting the metal atoms.The coordination number of one rare earth ion is nine,with the geometry of a distorted tricapped trigonal prism,the other is eight,with the geometry of a distorted dicapped trigonal prism.