Multicomponent density-functional theory for electrons and nuclei
Abstract
We present a general multicomponent density-functional theory in which electrons and nuclei are treated completely quantum mechanically, without the use of a Born-Oppenheimer approximation. The two fundamental quantities in terms of which our theory is formulated are the nuclear N -body density and the electron density expressed in coordinates referring to the nuclear framework. For these two densities, coupled Kohn-Sham equations are derived, and the electron-nuclear correlation functional is analyzed in detail. The formalism is tested on the hydrogen molecule H2 and its positive ion H2+ , using several approximations for the electron-nuclear correlation functional.
- Publication:
-
Physical Review A
- Pub Date:
- August 2008
- DOI:
- 10.1103/PhysRevA.78.022501
- Bibcode:
- 2008PhRvA..78b2501K
- Keywords:
-
- 31.15.E-;
- 31.15.A-;
- 71.10.-w;
- Density-functional theory;
- Ab initio calculations;
- Theories and models of many-electron systems