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

Summary.

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 MI₃[OOCCH₂CH(NH₂)CO]_2.5 · 2.5H₂O (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, α = 94.46°, β = 99.76° and γ = 100.1° for the complex of antimony and a = 0.9756 nm, b = 1.4560 nm, c = 1.9875 nm, α = 94.18°, β = 97.25° and γ = 101.16° 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.