| Abstract: | The crystal structure of the gold-bronce coloured, metallic NaHg, which was already determined earlier, is characterized by nearly square planar Hg4 clusters condensed to zig-zag chains via common edges. We discuss the hitherto unknown relation of the orthorhombic NaHg structure to the CsCl type (B2). and present calculations of the electronic structures for the hypothetical B2 structure as well as for the real orthorhombic structure by means of the relativistic LMTO method. A clear tendency is observed towards a population of the mercury 6 p-states, which are empty in the free atom in its ground state. This population is the most important contribution to the bonding between the mercury atoms in the cluster chains. Thus the simple chemical picture, whereafter a partial electron transfer should take place from the electropositive sodium to mercury, is in accordance with the calculation results. |
