Systematic generation of relativistic Gaussian basis sets

A method for the Gaussian basis set generation for molecular relativistic D irac-Fock calculations is proposed. The basis set exponents are obtained in the process of stochastic optimization (a hybrid of simplex and simulated annealing optimization techniques has been employed) of a functional define d as the sum of squares of differences between the numerical relativistic a tomic wave functions and the wave functions obtained using the Gaussian fun ction expansion. After this pre-optimization step the exponents are refined by ordinary gradient energy-functional based procedure. The present method seems to be very effective and robust. As an example the optimized basis s ets of atoms from H (Z = 1) to Ar (Z = 18) are presented. Results of the Di rac-Fock calculations for all atoms under study are presented and compared with the numerical Dirac-Fock results and results obtained using the Gaussi an basis sets according to Okada et al.: J. Chem. Phys. 93 (1990) 5013.