TRANSFERABILITY OF A LOCAL PSEUDOPOTENTIAL BASED ON SOLID-STATE ELECTRON-DENSITY

Citation
F. Nogueira et al., TRANSFERABILITY OF A LOCAL PSEUDOPOTENTIAL BASED ON SOLID-STATE ELECTRON-DENSITY, Journal of physics. Condensed matter, 8(3), 1996, pp. 287-302
Citations number
47
Categorie Soggetti
Physics, Condensed Matter
ISSN journal
09538984
Volume
8
Issue
3
Year of publication
1996
Pages
287 - 302
Database
ISI
SICI code
0953-8984(1996)8:3<287:TOALPB>2.0.ZU;2-Y
Abstract
Local electron-ion pseudopotentials fitted to dominant density paramet ers of the solid state (valence, equilibrium avenge electron density a nd interstitial electron density) have been constructed and tested for sixteen simple metals. Calculated solid-state properties present litt le evidence of the need for pseudopotential non-locality, but this nee d is increasingly evident as the pseudopotentials are transferred furt her from their solid-state origins. Transferability is high for Na, us eful for ten other simple metals (K, Rb, Cs, Mg, Al, Ga, In, Tl, Sn, a nd Pb), and poor for Li, Be, Ca, Sr and Ba. In the bulk solid, we defi ne a predictor of transferability and check the convergence of second- order pseudopotential perturbation theory for bcc Na. For six-atom oct ahedral clusters, we find that the pseudopotential correctly predicts self-compressions or self-expansions of bond length with respect to th e bulk for Li, Na, Mg, and Al, in comparison with all-electron results ; dimers of these elements are also considered. For the free atom, we examine the bulk cohesive energy (which straddles the atomic and solid -state limits), the atomic excitation energies and the atomic density. For the cohesive energy, we also present the results of the simpler s tabilized jellium and universal-binding-energy-curve models. The neede d nonlocality or angular-momentum dependence of the pseudopotential ha s the conventional character, and is most strongly evident in the exci tation energies.