Cooperativity in Alcohol-Nitrogen Complexes: Understanding Cryomatrices through Slit Jet Expansions

Abstract

FTIR spectroscopy of supersonic expansions is used to characterize alcohol dimets with one, two, and several nitrogen molecules attached to them.The nitrogen coating causes progressive spectral downshifts of the OH stretching fondamentals which are related to and explain matrix isolation shifts. Comparison Of methanol, tert-butyl alcohol and ethanol as well as deuteratfon of methanol assist in the assignment. Alcohol monomers and trimers are significantly more resistant to nitrogen coating due to a lack of coopetativity and,dangling bonds respectively. In the case of ethanol, the role of conformational isomerism and combination bands is further elucidated. The exiaerimental findings help rationalize the anomalously small OH stretching,ditnetitatiort shift of methanol in the gas phase, in comparison to that of tert-butyl alcohol.