TY - JOUR

T1 - Electronic non-adiabatic states

T2 - Towards a density functional theory beyond the Born-Oppenheimer approximation

AU - Gidopoulos, Nikitas I.

AU - Gross, E. K.U.

PY - 2014/3/13

Y1 - 2014/3/13

N2 - A novel treatment of non-adiabatic couplings is proposed. The derivation is based on a theorem by Hunter stating that the wave function of the complete system of electrons and nuclei can be written, without approximation, as a Born-Oppenheimer (BO)-type product of a nuclear wave function, X(R), and an electronic one, ΦR(r), which depends parametrically on the nuclear configuration R. From the variational principle, we deduce formally exact equations for ΦR(r) and X(R). The algebraic structure of the exact nuclear equation coincides with the corresponding one in the adiabatic approximation. The electronic equation, however, contains terms not appearing in the adiabatic case, which couple the electronic and the nuclear wave functions and account for the electron-nuclear correlation beyond the BO level. It is proposed that these terms can be incorporated using an optimized local effective potential.

AB - A novel treatment of non-adiabatic couplings is proposed. The derivation is based on a theorem by Hunter stating that the wave function of the complete system of electrons and nuclei can be written, without approximation, as a Born-Oppenheimer (BO)-type product of a nuclear wave function, X(R), and an electronic one, ΦR(r), which depends parametrically on the nuclear configuration R. From the variational principle, we deduce formally exact equations for ΦR(r) and X(R). The algebraic structure of the exact nuclear equation coincides with the corresponding one in the adiabatic approximation. The electronic equation, however, contains terms not appearing in the adiabatic case, which couple the electronic and the nuclear wave functions and account for the electron-nuclear correlation beyond the BO level. It is proposed that these terms can be incorporated using an optimized local effective potential.

KW - Beyond Born-Oppenheimer

KW - Density functional theory

KW - Non-adiabatic effects

UR - http://www.scopus.com/inward/record.url?scp=84894231252&partnerID=8YFLogxK

U2 - 10.1098/rsta.2013.0059

DO - 10.1098/rsta.2013.0059

M3 - Article

AN - SCOPUS:84894231252

SN - 1364-503X

VL - 372

JO - Philosophical transactions. Series A, Mathematical, physical, and engineering sciences

JF - Philosophical transactions. Series A, Mathematical, physical, and engineering sciences

IS - 2011

M1 - 20130059

ER -