Lone Pairs as Chemical Scissors in New Antimony Oxychlorides, Sb₂ZnO₃Cl₂ and Sb₁₆Cd₈O₂₅Cl₁₄

Two new metal antimony oxychlorides, Sb₂ZnO₃Cl₂ and Sb₁₆Cd₈O₂₅Cl₁₄, have been synthesized by solid-state reactions using Sb₂O₃ and ZnCl₂ (or CdCl₂) as reagents. The structures of Sb₂ZnO₃Cl₂ and Sb₁₆Cd₈O₂₅Cl₁₄ have been determined by single-crystal X-ray diffraction. Both of the reported materials contain Sb³⁺ cations that are in an asymmetric coordination environment attributable to their stereoactive lone pair. Sb₂ZnO₃Cl₂ has a novel two-dimensional layered structure consisting of distorted ZnO₂Cl₂ tetrahedra and SbO₃ polyhedra. Sb₁₆Cd₈O₂₅Cl₁₄ exhibits a one-dimensional structure consisting of Sb³⁺−Cd²⁺−oxide rods, Cd²⁺−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: Sb₂ZnO₃Cl₂, orthorhombic, space group Pnma (No. 62), a = 17.124(4) Å, b = 5.5598(12) Å, c = 6.4823(14) Å, V = 617.2(2) ų, and Z = 4; Sb₁₆Cd₈O₂₅Cl₁₄, monoclinic, space group I2/m (No. 12), a = 14.251(3) Å, b = 3.9895(8) Å, c = 21.145(4) Å, β = 97.35(3)°, V = 1192.3(4) ų, and Z = 8.