希土季铵盐配合物的研究——Ⅴ.[(n-C_4H_9)_4N]_3Nd(NCS)_6的晶体结构研究

STUDIES ON RARE EARTH COMPLEXES OF QUATERNARY AMMONIUM SALT V. CRYSTAL AND MOLECULAR STRUCTURE OF TETRABUTYL AMMONIUM HEXAISO-THIOCYANATO NEODYMIUM [(C_4H_9)_4N]_3Nd(NCS)_6

合成了硫氰酸合希土酸四丁基季铵盐配合物,测定了它们的远红外光谱及部分配合物的中红外光谱,结果表明,配合物中的NCS^-是以氮原子与Ln^(3+)配位。用X射线单晶衍射法测定了[(n-C_4H_9)_4N]_3Nd(NCS)_6晶体的结构,结果表明,该晶体属单斜晶系,C_c空间群,晶胞参数为:a=25.188(8)(?),b=13.320(6)(?),c=25.322(8)(?),β=121.30(2)°,晶胞体积V=7258.9(?)~3,每一晶胞中有四个配合物分子,中心离子Nd^(3+)与六个来自NCS^-的氮原子配位,这六个氮位于配位正八面体的六个顶角上,构成配阴离子Nd(NCS)_6^(3-),它与三个[(n-C_4H_9)_4N]^+以静电引力结合成中心分子,所以晶体为离子型晶体。

The complexes of tetrabutyl ammonium hcxaisothiocyanato rare earths, have been synthesized. The crystal and molecular structure of [(C4H9)4N]3Nd(NCS)6 has been determined by single crystal X-ray diffraction techniques with a four circle diffractometer to a final R value of 0.12. The crystal is monoclinic with space group Cc. The unit cell parameters are: a=25.188(8)A, b= 13.320(6)A, c=25.322(8)A, β=121.30(2)°, Z = 4, V=7258.9A3, dcalc.=1.114g/cm3. The neodymium atom is coordinated by six nitrogen atoms from six isothiocyanate groups to form a complex anion, in which the nitrogen atoms take a distorted octahedron arrangement. The anion is counterbalanced by three [(C4H9)4N]+ cations in the outersphere of the complex through electrostatic attraction to form an ionic crystal. The average bond length of Nd-N is 2.432(20) A. The infrared spectra of this, series of complexes have been determined and discussed as well.