Investigation on the Coordinate Structures of the Rare Earth Metal Complexes with Edta and Cydta Ligands

摘要

The crystal and molecular structures of cydta(trans-1, 2-cyclohexanediaminetetraacetic acid) have been determined by single-crystal X-ray structure analyses. The reasons that REⅢ-edta and REⅢ-cydta complexes select different coordinate structures were discussed and illustrated through the comparison of the molecular and crystal structures between edta and cydta, (NH4)[Ⅲ(edta) (H2O)3]·5H2O and (NH4)[YⅢ(cydta)(H2O)2]·5H2O as well as (NH4)[GdⅢ(edta)(H2O)3]·5H2O and (NH4)[GdⅢ(cydta)(H2O)2]·5H2O complexes.