title: Improved perturbative treatment of electronic energies from a minimal-norm approach to many-body perturbation theory.
abstract: We propose a zeroth-order Hamiltonian for many-body perturbation theory based on the unitary decomposition of the two-particle reduced Hamiltonian. For the zeroth-order Hamiltonian constrained to be diagonal in the Hartree-Fock basis set, the two-particle reduced perturbation matrix is chosen to have a minimal Frobenius norm. When compared with the Møller-Plesset partitioning, the method yields more accurate second-order energies.
authors.affiliation: James Franck Institute and the Department of Chemistry, University of Chicago, Chicago, Illinois 60637, USA.
authors.forename: Tamás
authors.initials: T
authors.lastname: Juhász
authors.forename: David A
authors.initials: DA
authors.lastname: Mazziotti