Interpretation of hypsochromic and bathochromic shifts of vibrational frequencies of a cation exchanger

Structures of a representative fragment of a sulfocation exchanger in the form of alkali metal salts were optimized using the Gaussian-03 program package. Frequencies of stretching vibrations of the sulfo group were calculated for structures of the contact ion and hydrate-separated ion pairs. A comparison of the calculated and experimental values of hypsochromic (bathochromic) shifts of the frequencies of stretching vibrations of the sulfo group due to the cation field suggests that the ion pair in the studied systems dissociates. The calculated IR spectra of the representative fragment of the sulfocation exchanger can be used as calculated benchmarks in analyzing substances using expert systems.