FORMATION AND REDUCTION OF SEMICONDUCTOR-LIKE AGGREGATES OF SILVER-CARBOXY-ALKANE-THIOLATES IN AQUEOUS-SOLUTION

Abstract

AbstractIn slightly acidic solutions of Ag+ and carboxy‐methane‐thiol (CMT) or carboxy‐ethane‐thiol (CET), aggregates are formed whose absorption spectrum is significantly different from that of the monomeric silver‐carboxy‐alkane‐thiols. The build‐up of the aggregates occurs slowly. They develop a band at 335 nm (AgCMT) or 355 nm (AgCET), and simultaneously, acquire fluorescence. Silver is produced upon the photolysis of the aggregates. A very small amount of silver atoms deposited on the aggregates is sufficient to quench the fluorescence substantially. Both the absorption and fluorescence bands are blue‐shifted as the aggregates become smaller during photolysis or dissolution in alkalin..