THE CRYSTAL STRUCTURE OF RARE EARTH COMPLEX WITH AMINO ACIDS Ⅱ The Crystal Structure of Gtutamate Comptex of Erbium Perchtorate

摘要

The crystat structure of {[Er₂（L—Glu）₂（H₂O）₆]（ClO₄）₂·3H₂O)₂ has been studied by X-ray diffraction. The crystal is monoctinic with space group P2₁ and cell parameters a=19.987（3） , b=16.505（3） , c=11.040（2） , β=104.69（1）o, V=3538（1） , Z=2, Dc=2.29 g. cm-3, μ=53.2 cm-1, F（000）=2384. The asymmetric unit contains two complex motecules and four centre ions. Each erbium （Ⅲ） is coordinated by five oxygen donors from four different glutamates and four oxygen donors from the aqua ligand to form a nine coordination potyhedron. The mean distances of Er—0 （carboxylate） and Er—Ow are 2.439 and 2.41 respectivety. The finat R and Rw are 0.043 and 0. 058, respectivety.