Structure of high- and low-density amorphous ice

A nonstandard procedure is applied for deriving the partial pair correlation functions of high- and low-density amorphous ice, starting from two experimental total structure factors, applying the reverse Monte Carlo modeling technique. Our study suggests that the structures of these materials have been misinterpreted so far, regarding particularly the H-bonding distance at 1.8 Angstrom if consistency with diffraction results is required. The findings reported here imply that the microscopic structure of the low-density form is dominated by a considerable amount of H-bond disorder, this being the greatest difference from the high density form.