The vibrational spectrum of the water dimer: Comparison between anharmonic ab initio calculations and neon matrix infrared data between 14,000 and 90 cm-1

The infrared spectrum of the water dimer trapped in solid neon has been recorded up to the visible by improving significantly the experimental technique used in a previous paper [Y. Bouteiller, J.P. Perchard, Chem. Phys. 305 (2004) 1]. A total of 22 intramolecular transitions of the proton donor (PD) and 23 of the proton acceptor (PA) are now identified and assigned on the basis of O-16/O-18 isotopic shifts and of realistic anharmonicity corrections. From an ab initio determination of the potential energy a perturbation-resonance treatment has been carried out for each polyad P-n, n = 2-8. Finally combinations of intra + intermolecular transitions were identified and assigned on the basis of calculated anharmonicity coefficients. (C) 2011 Elsevier B.V. All rights reserved.