On the Cholesky Decomposition for electron propagator methods: General aspects and application on C60

摘要

To treat the electronic structure of large molecules by electron propagatormethods we developed a parallel computer program called P-RICD$\Sigma$. Theprogram exploits the sparsity of the two-electron integral matrix by usingCholesky decomposition techniques. The advantage of these techniques is thatthe error introduced is controlled only by one parameter which can be chosen assmall as needed. We verify the tolerance of electron propagator methods to theCholesky decomposition threshold and demonstrate the power of theP-RICD$\Sigma$ program for a representative example (C60). All decompositionschemes addressed in the literature are investigated. Even with moderatethresholds the maximal error encountered in the calculated electron affinitiesand ionization potentials amount to a few meV only, and the error becomesnegligible for small thresholds.