Hartree-Fock complete basis set limit properties for transition metal diatomics


Numerical Hartree-Fock (HF) energies accurate to at least 1 μhartree are reported for 27 diatomic transition-metal-containing species. The convergence of HF energies toward this numerical limit upon increasing the basis set size has been investigated, where standard nonrelativistic all-electron correlation consistent basis sets and augmented basis sets, developed by Balabanov and Peterson [J. Chem. Phys. 123, 064107 (2005)], were employed. Several schemes which enable the complete basis set (CBS) limit to be determined have been investigated, and the resulting energies have been compared to the numerical Hartree-Fock energies. When comparing basis set extrapolation schemes, those in the form of exponential functions perform well for our test set, with mean absolute deviations from numerical HF energies of 234 and 153 μ Eh, when the CBS limit has been determined using a two-point fit as proposed by Halkier [Chem. Phys. Lett. 302, 437 (1999)] on calculations of triple- and quadruple- basis set qualities and calculations of quadruple- and quintuple- basis set qualities, respectively. Overall, extrapolation schemes in the form of a power series are not recommended for the extrapolation of transition metal HF energies. The impact of basis set superposition error has also been examined. © 2008 American Institute of Physics.

Publication Title

Journal of Chemical Physics