IR absorption spectroscopy of water in CsLiB6O10 crystals

Polarized absorption spectra of CsLiB6O10 crystals have been measured between -186 and 25 °C in the 1500-7500 cm-1 wavenumber range. A series of absorption bands have been observed with intensities depending on the thermal history of the crystals. Three of them have been assigned as the fundamental H-O-H bending mode (d = 1650 cm -1), and symmetric and asymmetric OH stretching modes of the bound H2O molecule (?s = 3413 cm-1 and ? a = 3581 cm-1, respectively). Additional features in the 3800-4400, 4700-5300 and 6500-7100 cm-1 ranges have been interpreted as overtones and combinations of the fundamental H2O vibrations. The above assignments have been verified by detecting the isotopic replica of the bands in a crystal treated in D2O vapour atmosphere. The possible sites for the H2O molecule in the lattice have been deduced from polarization angle dependence measurements. Œ 2003 Elsevier B.V. All rights reserved.