高周期14族半金属元素-EDTAの結晶構造: 単核錯体から配位高分子まで

Abstract

A metallic chelate of ethylenediaminetetraacetic acid (EDTA) is usually represented as a discrete complex by coordination number (CN) 6. On the other hand, it has been elucidated in the cations of heavier group 14 elements (heavy tetrels) chelated by EDTA that they have various binding modes from monomeric structures to coordination polymers from X-ray crystallographic studies. Some of them were systematized in reviews; however, they uncover the whole heavy tetrels-EDTA complexes. Hence, the reported crystal structures of heavy tetrels-EDTA complexes with different counter cations and/or (pseudo)halogens, 3 of Ge(IV)-, 2 of Sn(II)-, 5 of Sn(IV)-, and 21 of Pb(IV)-EDTA (CN 5-8), are briefly summarized herein for showing a variety of bonding modes existing in the heavy tetrels-EDTA chelates.