CHARGE-TRANSFER WITHIN ZINTL IONS IN LIQUID METALLIC ALLOYS - A CLUSTER STUDY

Self-consistent field multiple scattering X alpha calculations of the electronic structure of Na4Pb4, K4Pb4 and Rb4Pb4 clusters have been pe rformed in order to investigate the charge transfer process from the a lkali atoms to the lead atoms. The structure assumed is that of an inn er Pb-4 tetrahedron surrounded by another, larger tetrahedron in which the alkali atoms lake positions opposite to the faces of the Pb-4 uni t. The total charge transfer to Pb-4 is about two electrons, half the amount normally assumed in the Zintl ion model of these clusters in so lid and liquid alloys.