title: On the calculation of complete dissociation curves of closed-shell pseudo-onedimensional systems via the complete active space method of increments.
abstract: The method of increments (MoI) has been employed using the complete active space formalism in order to calculate the dissociation curve of beryllium ring-shaped clusters Be(n) of different sizes. Benchmarks obtained through different quantum chemical methods including the ab initio density matrix renormalization group were used to verify the validity of the MoI truncation which showed a reliable behavior for the whole dissociation curve. Moreover we investigated the size dependence of the correlation energy at different interatomic distances in order to extrapolate the values for the periodic chain and to discuss the transition from a metal-like to an insulator-like behavior of the wave function through quantum chemical considerations.
authors.affiliation: Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Fertitta
authors.affiliation: Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Paulus
authors.affiliation: Strongly Correlated Systems "Lendület" Research Group, Wigner Research Centre for Physics, P.O. Box 49, Budapest, Hungary.
authors.forename: G
authors.initials: G
authors.lastname: Barcza
authors.affiliation: Strongly Correlated Systems "Lendület" Research Group, Wigner Research Centre for Physics, P.O. Box 49, Budapest, Hungary.
authors.forename: Ö
authors.initials: Ö
authors.lastname: Legeza