Maple procedures for the coupling of angular momenta. VIII. Spin-angular coefficients for single-shell configurations

摘要

Matrix elements of physical operators are required when the accurate theoretical determination of atomic energy levels, orbitals and radiative transition data need to be obtained for open-shell atoms and ions. The spin-angular part for these matrix elements is typically based on standard quantities such as matrix elements of the unit tensor, the (reduced) coefficients of fractional parentage as well as a number of other reduced matrix elements concerning various products of electron creation and annihilation operators. Therefore, in order to facilitate the access to the matrix elements of one- and two-particle scalar operators, we present here an extension to the RACAH program for the full set of standard quantities and the pure spin-angular coefficients in LS- and jj-couplings. A flexible notation is introduced for defining and manipulating the electron creation and the electron annihilation operators. This will allow us to solve successfully various angular momentum problems in atomic physics.