KOHN-SHAM ANALYTIC ENERGY 2ND DERIVATIVES WITH THE GAUSSIAN VERY FASTMULTIPOLE METHOD (GVFMM)

The first application of the Gaussian very fast multipole method (GvFM M) to the calculation of molecular energy second derivatives of Kohn-S ham (KS) density functional theory (DFT) is reported. The GvFMM is use d both in the solution of the coupled-perturbed KS (CPKS) equations an d in the calculation of electron-electron repulsion integral second de rivatives. We present benchmark tests on C24H12 and C54H18 using 3-21G and 6-31G basis sets that show modest improvements of speed for the formation of J((X)) (the Coulomb matrix formed from derivatives of the basis functions) and the integral second derivatives.