A New Electron-nucleus Correlation Functional forMulticomponent Density Functional Theory

Abstract

A new Colle-Salvetti type electron-nucleus correlation functional for multicomponent density functional theory is proposed. The new functional is derived from an electron-nucleus correlation wavefunction using only simple and reasonable physical corrections with only one fitted parameter. By calculating 18 small hydrogen-containing molecules, this correlation functional is found to quantitatively evaluate these electron-proton correlation energies. The strategy taken in this development is applicable not only to electron-proton correlations but also to electron-other nucleus correlations and even to correlations between electron and other particles like electron-muon and electron-positron correlations.