VIBRATIONAL SPECTROSCOPIC STUDIES OF THE STRUCTURE OF SPECIES DERIVEDFROM THE CHEMISORPTION OF BISULFATE ANION ON A PT(111) SINGLE-CRYSTALELECTRODE

The structure of bisulfate anion adsorbed on a Pt(111) surface was stu died by infrared spectroscopy as well as an ab initio molecular orbita l calculation. The calculation predicted the structure and vibrational frequencies of the anion. The band assignments in the infrared and Ra man spectra of KHSO4 were carried out by comparing the observed freque ncies of the bisulfate anion with those of the calculated values. The single absorption band of bisulfate anion adsorbed on a Pt(111) surfac e showed a large frequency shift against a potential change (140 cm-1 V-1). The anion chemisorbed through tridentate oxygen coordination on the surface and the band was assigned to the symmetric SO3 stretching mode.