FORMIC-ACID ADSORPTION ON SILVER FILMS - THE CREATION OF POLYMERIC ADLAYERS

The adsorption of formic acid on evaporated silver films was studied b y transmission infrared spectroscopy. These studies reveal that adsorp tion of molecular formic acid on clean silver surfaces proceeds direct ly into a polymeric phase, signified by substantial H-bonding interact ions. There is no evidence of either the monomeric or dimeric species, even at monolayer coverages. The infrared spectra of multilayers form ed on clean silver films show that the polymer chains adopt the beta-c rystalline structure. Adsorption of formic acid on oxygen-doped silver films results in O-H bond scission to yield the formate species in th e monolayer regime. Interestingly, multilayers of formic acid condense d on this formate layer now consist of polymeric chains in an ordered alpha-crystalline structure.