Generation, contraction, and polarisation of Gaussian basis sets for atomic and molecular calculations using the generator coordinate method with polynomial discretisation: atoms from Na through Cl.

The polynomial Generator Coordinate Hartree-Fock Gaussian basis sets, pGCHF, for the atoms Na, Mg, Al, Si, P, S, and Cl were generated using the generator coordinate method based on polynomial integral expansion to discretise the Griffin-Wheeler-Hartree-Fock equations. The pGCHF basis sets were contracted with the CONTRACT program based on the Davidson contraction model through which a set of 9s8p functions for the atoms Na through Cl were obtained. Polarisation exponents generated using the POLARIZATION program were added to the contracted pGCHF Gaussian basis sets.

On polarization functions for Gaussian basis sets.

In this work, we introduce a technique to choose polarization functions directly from the primitive set of Gaussian exponent without the necessity to optimize or even reoptimized them. For this purpose, initially, we employed Gaussian basis sets generated by using the Polynomial Generator Coordinate Hartree-Fock (PGCHF) method, and later we extended our technique to the cc-pVQZ and pc-3 Gaussian basis sets in order to show how our technique works and how good it is. Using the new polarized basis sets, from our technique, total electronic energies, equilibrium geometries, and vibrational frequencies were calculated for a set of molecules containing atoms from H(Z = 1) to Ba(Z = 56).