The infrared spectra of monomeric bicarbonate ions with hydrogen, deuterium, carbon‐12, and carbon‐13 isotopes have been measured. The ions were isolated in potassium halide matrices as thermal decomposition products of the normal, polymeric potassium or sodium bicarbonate salts. A normal coordinate analysis was carried out and a set of modified valence force constants was obtained which fit the observed isotopic frequencies with an average error of 0.8%. The barrier to rotation of the hydroxyl group was estimated to be 15.8 kcal/mole and a value of −35 cal/deg·mole was calculated for the entropy of hydration of the ion at 25°C.
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© 1965 American Institute of Physics.
1965
American Institute of Physics
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