Study of some silver‐thiol complexes and polymers: Stoichiometry and optical effects

The silver complexes of various thiols of low molecular weight have been studied by amperometric and spectrophotometric titrations. Cysteine and cysteamine form complexes with silver containing up to 1.5 Ag + /—SH. The ligands participating in the binding of silver are the —SH and amino groups. Under some conditions it was found that 1:1 thiol‐silver polymers were formed. These polymers probably have the general structure AgS(R)AgS(R). Some of them were prepared in pure form and subjected to various studies. Molecular weight determinations of the cysteine‐silver and glutathione‐silver polymers yielded values of 4000–7000 daltons. Studies on the UV absorption characteristics revealed that all of the polymers showed some type of regular band pattern. The cysteamine‐silver polymer is able to sensitize photographic emulsions.