The National Institute of Standards and Technology (NIST) has initiated a project to generate reference data for electronic structure calculations using the local-density approximation (LDA) and its variants. The project aims to provide benchmark data comparable to traditional quantum chemistry methods, with a target accuracy of 1 microHartree unit for total energies.
The first set of results includes total energies and orbital energy eigenvalues for the ground-state configurations of all atoms and singly-charged cations with atomic number Z ≤ 92, computed in four standard approximations using the exchange-correlation energy functional of Vosko, Wilk, and Nusair. The results have been obtained through extensive testing and comparison of results from several independent codes and reproduced on different computer models to eliminate machine dependence.
The project will help distinguish uncertainties arising from numerical implementation from those inherent in the basic formalism, particularly as density-functional approaches become more widespread in solving very large problems.
Keywords: ab initio, density-functional, exchange-correlation
