POLIR: polarizable, flexible, transferable water potential optimized for IR spectroscopy.

A polarizable, flexible and transferable potential for water, POLIR, is presented. In addition to providing a good description of the usual structural and kinetic properties, POLIR correctly describes the vibrational frequencies, absolute infrared intensities, and HOH angle in clusters, liquid water, and ice, offering the possibility of a comprehensive classical theory of vibrational spectroscopy. The high degree of transferability suggests applications to solvation and to water that is confined, interfacial, and under the extreme conditions encountered in the geological and planetary sciences.