Lone pairs as chemical scissors in new antimony oxychlorides, Sb2ZnO3Cl2 and Sb16Cd8O25Cl14

Inorg Chem. 2010 Mar 15;49(6):2990-5. doi: 10.1021/ic902493r.

Abstract

Two new metal antimony oxychlorides, Sb(2)ZnO(3)Cl(2) and Sb(16)Cd(8)O(25)Cl(14), have been synthesized by solid-state reactions using Sb(2)O(3) and ZnCl(2) (or CdCl(2)) as reagents. The structures of Sb(2)ZnO(3)Cl(2) and Sb(16)Cd(8)O(25)Cl(14) have been determined by single-crystal X-ray diffraction. Both of the reported materials contain Sb(3+) cations that are in an asymmetric coordination environment attributable to their stereoactive lone pair. Sb(2)ZnO(3)Cl(2) has a novel two-dimensional layered structure consisting of distorted ZnO(2)Cl(2) tetrahedra and SbO(3) polyhedra. Sb(16)Cd(8)O(25)Cl(14) exhibits a one-dimensional structure consisting of Sb(3+)-Cd(2+)-oxide rods, Cd(2+)-chloride double chains, and isolated Cl(-) ions. Complete separation of the halophile and chalcophile moieties is observed from the reported materials. Detailed structural analysis, IR spectra, thermogravimetric analysis, ion-exchange reactions, and dipole moment calculations are presented. Crystal data: Sb(2)ZnO(3)Cl(2), orthorhombic, space group Pnma (No. 62), a = 17.124(4) A, b = 5.5598(12) A, c = 6.4823(14) A, V = 617.2(2) A(3), and Z = 4; Sb(16)Cd(8)O(25)Cl(14), monoclinic, space group I2/m (No. 12), a = 14.251(3) A, b = 3.9895(8) A, c = 21.145(4) A, beta = 97.35(3) degrees, V = 1192.3(4) A(3), and Z = 8.