A new configuration selection method for configuration interaction calculations

The recently proposed stochastic diagonalization method is applied to the ab initio quantum chemistry configuration interaction problem. In this context it can be viewed as a multi-reference CI method with dynamic selection of important configurations. The method is compared with other methods and tested by calculations on a number of small molecular systems for which accurate results are available. A calculation on the Cr2 dimer is presented to show the capability of the algorithm to find short expansions of molecular wavefunctions