The Two-Electron Homopolar Chemecal Bond;Hydrogen

摘要

The correlation energy of the hydrogen molecule is considered as related to the He atom and to the infinitely separated atoms, and it is shown that one can obtain a con¬sistent qualitative picture of the electron-electron inter¬action in the molecular bond in this way. Previous approximate wave functions for hydrogen are analysed quantitatively into approximate natural spin orbital functions with particular attention to the corresponding occupation numbers. The ana¬lysis demonstrates 1) the very great similarity of all such trial wave functions, 2) the largely molecular orbital nature of the wave function, 3) the great similarity between the molecular orbital and valence bond functions, and 4) the necessity for allowing for angular correlation of the electrons. Finally the analysis shows very clearly that the concepts of "covalent" and "ionic" "character", at least as applied to the two-electron homopolar chemical bond, have no real significance and should be abandoned.