# Program to calculate pure angular momentum coefficients in jj-coupling ☆

## Description

Abstract A program for computing pure angular momentum coefficients in relativistic atomic structure for any scalar one- and two-particle operator is presented. The program, written in Fortran 90/95 and based on techniques of second quantization, irreducible tensorial operators, quasispin and the theory of angular momentum, is intended to replace existing angular coefficient modules from GRASP92. The new module uses a different decomposition of the coefficients as sums of products of pure angular mome... Title of program: ANCO Catalogue Id: ADOO_v1_0 Nature of problem The matrix elements of a one-electron tensor operator A^k of rank k with respect to a set of configuration state functions |gammai Ji> can be written Sigma ab tij^k(ab)(a|A^k|b) where the angular coefficients tij^k(ab) are independent of the operator A^k, i, j are CSF labels and a, b run over the relevant interacting orbital labels. Similarly, the matrix elements of the Dirac-Coulomb Hamiltonian can be written in the form Sigma ab tij^0(ab)(a|H^D|b) + Sigma k Sigma abcd Vij^k(abcd)X^k(abcd), whe ... Versions of this program held in the CPC repository in Mendeley Data ADOO_v1_0; ANCO; 10.1016/S0010-4655(01)00213-2 ADOO_v2_0; ANCO(2); 10.1016/S0010-4655(02)00589-1 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2019)