Towards a spin-adapted coupled-cluster theory for high-spin open-shell states.
A spin-adapted coupled-cluster (SA-CC) scheme based on the additional consideration of spin constraints is proposed for the quantum chemical treatment of high-spin open-shell cases. Its computational feasibility is demonstrated via a pilot implementation within the singles and doubles approximation. Test calculations indicate that the suggested SA-CC scheme provides results of similar accuracy as the more traditional schemes without spin adaptation.
Heckert
Miriam
M
Institut für Physikalische Chemie, Universität Mainz, D-55099 Mainz, Germany.
Heun
Oliver
O
Gauss
Jürgen
J
Szalay
Péter G
PG