Synthesis, Crystal Structure and Thermal Decomposition of the New Cadmium Selenite Chloride, Cd(4)(SeO(3))(2)OCl(2)

A synthetic study in the Cd-Se-O-Cl system led to formation of the new oxochloride compound Cd(4)(SeO(3))(2)OCl(2) via solid state reactions. The compound crystallizes in the orthorhombic space group Fmmm with cell parameters a = 7.3610(3) Å, b = 15.4936(2) Å, c = 17.5603(3) Å, Z = 8, S = 0.969, F(000) = 2800, R = 0.0185, R(w) = 0.0384. Single crystal X-ray data were collected at 293 K. The crystal structure can be considered as layered and the building units are distorted [Cd(1)O(6)] octahedra, distorted [Cd(2)O(8)] cubes, irregular [Cd(3)O(4)Cl(2)] polyhedra and SeO(3)E trigonal pyramids. There are two crystallographically unique Cl atoms that both are half occupied. Thermogravimetric studies show that the compound starts to decompose at 500°C. The crystal structure of the new compound is closely related to the previously described compound Cd(4)(SeO(3))(2)Cl(4)(H(2)O).