A detailed assignment of the O–H stretching bands of ice I

Abstract

A detailed assignment of the infrared and Raman O–H stretching bands of disordered ice Ih and Ic is proposed. It is based on the assumptions that the spectra of disordered ice Ic are closely related to those of ordered ice Ic, and that the spectra of the as yet unrealized ordered ice Ic can be predicted from the spectra of ice VIII. The supposed similarity between the spectra of ordered and disordered ice Ic is justified by the observed similarity of the spectra of ice VIII and VII, which are respectively ordered and disordered forms of the same structure and are closely related to ordered and disordered ice Ic. The assignment takes into account the intermolecular coupling, which is particularly strong for the ν1 vibrations but weak for the v3, and the TO–LO splitting, particularly of the v3 vibrations, which is shown to be required by the high infrared intensity. The infrared and Raman bands of amorphous ice have been assigned by analogy with the assignments of ice I.