Jj. Max et C. Chapados, Interpolation and extrapolation of infrared spectra of binary ionic aqueous solutions, APPL SPECTR, 53(12), 1999, pp. 1601-1609
Factor analysis of the attenuated total reflection (ATR) absorbance spectra
of aqueous saline solutions has shown that these spectra are linear combin
ations of two eigenspectra: pure water and salt-solvated water. This paper
outlines the general equations needed to formalize these experimental resul
ts. In the case of binary salts in aqueous solutions, the equations allow i
nterpolation and extrapolation from one concentration to another. The accur
acy of the calculation method was adequately verified on aqueous solutions
of KCl. The equations made it possible to calculate the ATR absorbance spec
trum of a "pure" KCl-solvated water. The latter, which contains no ordinary
water, enabled us to determine that solvated water forms clusters made up
of a pair of ions with five molecules of water. The same results were obtai
ned with NaCl aqueous solutions.