Proposed modelling of the X-ray intensities in high-pressure crystalline phases of methane and silane

Abstract

A one-parameter model generalizing that of Banyard and March for the vapour phase of methane is first applied to interpret semi-quantitatively the measured X-ray intensities from a rhombohedral phase of compressed solid CH₄. Due to current interests in silane under pressure, X-ray intensities are also predicted for SiH₄, the parameter of the model depending of course on the degree of compression. A possible future direction is briefly proposed.

Keywords:

• CH₄ (methane)
• SiH₄ (silane)
• X-ray scattering

Acknowledgements

The authors thank Professor C. Van Alsenoy for useful discussions and correspondence. NHM wishes to acknowledge that his contribution to this study was made as a result of the stimulating atmosphere provided by the Joint 21st AIRAPT and 45th EHPRG International Conference on High Pressure Science and Technology, held in Catania, September 2007. NHM also wishes to thank Professors Porto and Pucci for very generous hospitality.