Analytic calculation of the diagonal Born-Oppenheimer correction within configuration-interaction and coupled-cluster theory.
Schemes for the analytic calculation of the diagonal Born-Oppenheimer correction (DBOC) are formulated and implemented for use with general single-reference configuration-interaction and coupled-cluster wave function models. Calculations are reported to demonstrate the convergence of the DBOC with respect to electron-correlation treatment and basis set as well as to investigate the size-consistency error in configuration-interaction calculations of the DBOC. The importance of electron-correlation contributions to the DBOC is illustrated in the computation of the corresponding corrections for the reaction energy and activation barrier of the F + H2 --> FH + H reaction as well as of the atomization energy for trans-butadiene.
Gauss
Jürgen
J
Institut für Physikalische Chemie, Universität Mainz, D-55099 Mainz, Germany. gauss@uni-mainz.de
Tajti
Attila
A
Kállay
Mihály
M
Stanton
John F
JF
Szalay
Péter G
PG