The role of electron correlations in the binding properties of Ca, Sr, and Ba

J Phys Condens Matter. 2010 Jul 14;22(27):275504. doi: 10.1088/0953-8984/22/27/275504. Epub 2010 Jun 23.

Abstract

In order to apply wavefunction-based correlation methods to solids it is necessary to have reliable Hartree-Fock (HF) results for the infinite system of interest. We performed Hartree-Fock calculations for the group 2 heavy alkali-earth metals Ca, Sr, and Ba. For that, basis sets of valence-double-ζ quality have been optimized for the periodic systems. In all cases small-core pseudopotentials were used to deal with the scalar-relativistic effects. We determine the cohesive energies, the equilibrium volumes and the bulk moduli of the systems at the Hartree-Fock level and compare them with experimental data as well as the results of density functional theory calculations. Relativistic effects in the case of Ba are estimated by using a non-relativistic pseudopotential. The comparative HF versus the density functional theory (DFT) study of the electronic structures of Ca, Sr, and Ba has been performed.

MeSH terms

  • Algorithms
  • Barium / chemistry*
  • Calcium / chemistry*
  • Computer Simulation
  • Electrons
  • Metals / chemistry
  • Physics / methods
  • Pressure
  • Software
  • Strontium / chemistry*

Substances

  • Metals
  • Barium
  • Calcium
  • Strontium