X-Ray Diffraction Study of the Cubic Phase of Ice

Abstract

An x-ray diffraction study has been made of the cubic phase of ice previously reported by König from electron diffraction work. Cubic ice could be obtained only by direct crystallization from the vapor onto surfaces at low temperature. Condensation rate and surface conditions are critical variables in the formation of cubic ice. Powdered mixtures of cubic and hexagonal ice were studied at —190° and —130°C. The powder x-ray patterns confirm the diamond structure for the oxygen atoms; the cubic cell edge is a=6.37 ±0.02 A at —190°C.