Relativistic band structure of thorium

The electronic band structure of f.c.c. thorium of actinium series has been calculated usinq Relativistic Augmented Plane Wave method. The potential is calculated from the new relativistic charge density of Liberman. The interesting feature of the new potential is that even when the Slater exchange approximation is included, the f-bands are not interfering with the s-d bands. This enables one to do the band structure calculation without removing the f-band contribution from the calculation itself. In an earlier work, Loucks and Gupta have to remove the f-band contribution in the calculation of cfsub(k)/gsub(k) in order to avoid the f-band interference. This procedure is unrealistic even though it gives reasonable results. The band structure is also calculated using a crystal potential which includes correlation. The f-bands are found to move well above the filled levels. Further calculations are in progress. (author)