New Slater-type orbital basis sets for first row transition elements

Abstract

A comparative study, at the atomic level, of the quality of eight Slater-type orbitals (STO) basis sets has been carried out for the first row transition elements. Two new basis sets are proposed for these elements: the β1 basis set (small-size-type) and the α2 basis set (intermediate-size-type). Both basis sets have been developed according to the so-called δ test [J. A. Sordo and L. Pueyo, Int. J. Quantum Chem. XXVIII, 687 (1985)]. The results suggest that the errors detected by means of the δ test could be responsible for the wrong ordering predicted by 2-ζ (and lower quality basis sets) for the 4s13d10 (2S) and 4s23d9(2D) states in Cu. All the quality tests used indicated that β1 basis sets would be very appropriate for performing economical molecular calculations and that α2 basis sets, with only one STO more than 2-ζ basis sets, would provide atomic results near the Hartree–Fock limit.