ON THE STATISTICAL DISTRIBUTION OF COPPER IONS IN THE STRUCTURE OF β-CHALCOCITE

抄録

The crystal structure of β-chalcocite was determined by employing the X-ray diffraction data taken at 144°C. From its three-dimensional distribution of electron density, it was concluded that copper ions are distributed in the structure among several sites in the interstices of the array of sulphurions in hexagonal closest-packing. This conclusion is in good agreement with the recent study on the same structure made by Buerger and Wuensch. Two dimensional projections of electron density in the crystal were also worked out at four different temperatures. The statistical distribution of copper ions revealed in these experimental results is explained by an assumption that these ions travel via sites at which they form s-p hybrid covalent bonds with the neighbouring sulphur ions.