Spectra of dangling OH bonds in amorphous ice: Assignment to 2- and 3-coordinated surface molecules

Abstract

Interpretation is provided for the recently measured stretch spectra of the dangling OH and OD bonds in amorphous ice deposits. The spectral bands are doublets; the higher and the lower frequency feature of each doublet is assigned respectively to 2- and 3-coordinated water molecules on the surface. The assignment is based on combined computational and experimental evidence. Annealing of 2-coordinated surface molecules is demonstrated in a simulated amorphous H2O cluster.