U. Nickel et al., CHARGE-TRANSFER LIKE COMPLEXES OF ORGANIC-DYES ADSORBED AT COLLOIDAL SILVER STUDIED BY CYCLIC VOLTAMMETRY, UV-VIS AND SERS SPECTROSCOPY, Berichte der Bunsengesellschaft fur Physikalische Chemie, 101(1), 1997, pp. 41-49
Citations number
21
Categorie Soggetti
Chemistry Physical
Journal title
Berichte der Bunsengesellschaft fur Physikalische Chemie
After adding cationic dyes like oxazine 170, malachite green, and crys
tal violet to a solution of colloidal silver sometimes an absorption b
and appears at wavelengths > 750 nm which is neither caused by the mon
omeric dye nor by a coagulation of the colloid. Based on electrochemic
al measurements this new absorption band is assigned to a chinhydron-l
ike adsorption geometry of the dye. Usually this band is only observed
at low concentration of the dye, whereas al higher concentration the
formation of H-aggregates occurs. There seems to be a relationship bet
ween the intensity of this band and the SERS activity.