Synthesis and characterization of aspartic acid complexes of antimony and bismuth triiodide.

New bioinorganic complexes of the aspartic acid with the antimony or bismuth triiodide were synthesized by a direct solid-solid reaction at room temperature. The formula of the complex is MI(3)[OOCCH(2)CH(NH(2))CO](2.5) x 2.5H(2)O (M = Sb, Bi). The complex may be a dimer with bridge structure. The crystal structure of the complexes belongs to a triclinic system. The lattice parameters are a = 0.9883 nm, b = 1.4284 nm, c = 2.0114 nm, alpha = 94.46 degrees , beta = 99.76 degrees and gamma = 100.1 degrees for the complex of antimony and a = 0.9756 nm, b = 1.4560 nm, c = 1.9875 nm, alpha = 94.18 degrees , beta = 97.25 degrees and gamma = 101.16 degrees for the complex of bismuth. The infrared spectra and thermal analyses can demonstrate the complex formation between the aspartic acid and the antimony or bismuth ion.