DFT study of the electronic structure of Saccharin, Thiosaccharin and their respective ions. Effects of metal

M.M. BRANDA; N.J. CASTELLANI; S.H. TARULLI; O. V. QUINZANI; E. J. BARAN; R. H. CONTRERAS

INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY

Wiley

Año: 2002 vol. 89 p. 525 - 534

0020-7608

A rationalization of the conspicuous different abilities of saccharin and thiosaccharin to form coordination compounds with the first series of transition metal elements and to interact with heavy metal cations is sought. Their electronic molecular structures as well as those of their respective ions, are compared performing NBO analyses of the four species. Upon deprotonation, a) the negative charge at the N atom in saccharin is almost constant while it decreases in thiosaccharin, and b) the negative charge at the mono-coordinated chalcogen atom is notably more increased in the later than in the former. Apparently, in thiosaccharin a) difficults the coordination with the first series of transition metal elements, and b) favors its experimentally observed interaction with heavy metal cations like cadmium, lead, mercury, silver and thallium.