Abstract
We report a variational and diffusion quantum Monte Carlo study of sodium. Pseudopotentials are used to represent the ion cores, and core-valence correlation effects are included by using a core polarization potential. When the core polarization potential is included we obtain an excellent value for the first ionization energy of the atom and a good value for the cohesive energy of the solid. Variational calculations of the occupied bandwidth give larger values than experiment, in agreement with recent sophisticated many-body calculations. Including the core polarization potential narrows the bandwidth slightly.
- Received 19 May 2003
DOI:https://doi.org/10.1103/PhysRevB.68.165103
©2003 American Physical Society