I. Ovcharenko et al., Soft pseudopotentials for efficient quantum Monte Carlo calculations: FromBe to Ne and Al to Ar, J CHEM PHYS, 114(18), 2001, pp. 7790-7794
We have developed "soft" ab initio Hartree-Fock pseudopotentials for Be-Ne
and Al-Ar that avoid singularities at the electron-nuclear cusp. The absenc
e of these singularities is a desired feature for quantum Monte Carlo (QMC)
calculations, because it considerably reduces local energy fluctuations wh
en sampling the QMC wave function. A modified procedure for obtaining soft
pseudopotentials is introduced. Stability of QMC calculations with the deve
loped pseudopotentials is demonstrated by the ability to use larger time st
eps for comparable accuracy with the previously available pseudopotentials.
As expected, ionization potentials and electron affinities computed using
the present approach compare very favorably with other Hartree-Fock pseudop
otential methods. (C) 2001 American Institute of Physics.