A FT-IR absorption analysis of vibrational properties of water encaged in NaA zeolites: evidence of a “structure maker” role of zeolitic surface

We performed, in the O-H stretching region, Fourier-transform Infrared (FT-IR) Absorption measurements for investigating the vibrational dynamics on water confined in NaA zeolite, vs. temperature and for different hydration percentages. The spectral substructure of the O-H stretching band is explained postulating the existence of three major components centred at ∼3290 cm-1 (ω 1), ∼3470 cm-1 (ω 2), ∼3590 cm-1 (ω 3), with different dynamical properties traced over the full T-range investigated