ATOMCI is a Configuration Integration (CI) program for atoms in the Russell-Saunders coupling scheme. The method for the calculation of the matrix elements is based on the vacuum expectation value of tensor operators and on the recoupling transformation coefficients.
Any publication based upon results obtained from this material MUST include the following attribution: "This work is based, in part, on results from the ATOMCI package." and refer to the following papers:
F. Sasaki, Int. J. Quantum Chem. Vol.8, pp.605 (1974).
F. Sasaki, M. Sekiya, T. Noro, K. Ohtsuki, and Y Osanai, "Non--Relativistic Configuration Interaction Calculations for Many-Electron Atoms: ATOMCI", pp.163--219 : Methods and Techniques in Computational Chemistry in METECC-94 edited by E. Clementi (ETEF, Cagliari, 1993).
The first version of ATOMCI was prepared in 1972 at the IBM Research Center in San Jose. In the present version of ATOMCI the routines for the generation of the energy expression have been completely rewritten to increase the speed and decrease the disk space requirements of the code. Routines for the perturbative selection of the configurations have been implemented, and high performance code for the diagonalization, written by N. Kosugi, has been used. Dr. Nagashima helped in preparing the ATGEN utility.