Pure spin-angular momentum coefficients for non-scalar one-particle operators in jj-coupling Original Research Article

A revised program for generating the spin-angular coefficients in relativistic atomic structure calculations is presented. When compared with our previous version [G. Gaigalas, S. Fritzsche and I.P. Grant, Comput. Phys. Comm. 139 (2001) 263], the new version of the Anco program now provides these coefficients for both, scalar as well as non-scalar one-particle operators as they arise frequently in the study of transition probabilities, photoionization and electron capture processes, the alignment transfer through excited atomic states, collision strengths, and in many other investigations. The program is based on a recently developed formalism [G. Gaigalas, Z. Rudzikas and C.F. Fischer, J. Phys. B 30 (1997) 3747], which combines techniques from second quantization in coupled tensorial form, the theory of quasispin, and the use of reduced coefficients of fractional parentage, in order to derive the spin-angular coefficients for complex atomic shell structures more efficiently. By making this approach now available also for non-scalar interactions, therefore, studies on a whole field of new properties and processes are likely to become possible even for atoms and ions with a complex structure.