The Effect of Temperature on the Formation of Bismuth(III) Monocysteine and Monothiosemicarbazide Complexes

摘要

The stability constants of monocomplexes of cysteine (H2Cys) and thiosemicarbazide (Tsc) with bismuth(III) at 288, 313 and 333 K in 0.5 M HC1O4 and an ionic strength of 2(NaClO4) were determined by spectrophotometry. On the basis of a substantial difference in the stability constants of bismuth monocomplexes with H2Cys and Tsc, the high acidity of the investigated solutions, and known coordination modes of these ligands in crystalline compounds, the formation of Bi(HCys-O,S)~(2+) and Bi(Tsc-N, S)~(3+) is suggested.