Convergence behaviour of multireference perturbation theory: an indicator
- 1 April 1997
- journal article
- research article
- Published by Taylor & Francis in Molecular Physics
- Vol. 90 (6) , 1007-1012
- https://doi.org/10.1080/002689797172002
Abstract
An approach to investigate the convergence behaviour of a (multireference) Møller-Plesset perturbation series is proposed in which the series is evaluated up to arbitrary order without reference to excitations beyond doubles. It is shown that this approach qualitatively reproduces the convergence behaviour of the complete perturbation series for stretched H2 molecules and H2O molecules. The MRMP approach does show improved convergence characteristics compared with single reference MP for stretched H2 molecules. Applications of the approach to O2 at 4·0 a 0, and N2 at 5·0 a 0 show that the MRMP series is divergent for these cases. Furthermore, in the latter case it was found that the multireference series shows much stronger divergence than the single reference series.Keywords
This publication has 20 references indexed in Scilit:
- Third-order multireference perturbation theory The CASPT3 methodMolecular Physics, 1996
- Second-order perturbation theory with a complete active space self-consistent field reference functionThe Journal of Chemical Physics, 1992
- Second-order perturbation theory with a CASSCF reference functionThe Journal of Physical Chemistry, 1990
- Valence bond theory: Progress and prospectsInternational Journal of Quantum Chemistry, 1990
- Super-matrix methodsComputer Physics Communications, 1989
- Consistent generalization of the Møller-Plesset partitioning to open-shell and multiconfigurational SCF reference states in many-body perturbation theoryChemical Physics Letters, 1987
- Molecular orbital theory of the properties of inorganic and organometallic compounds 4. Extended basis sets for third‐and fourth‐row, main‐group elementsJournal of Computational Chemistry, 1986
- The calculation of higher-order energies in the many-body perturbation theory seriesChemical Physics Letters, 1985
- Self-consistent molecular-orbital methods. 22. Small split-valence basis sets for second-row elementsJournal of the American Chemical Society, 1982
- The iterative calculation of a few of the lowest eigenvalues and corresponding eigenvectors of large real-symmetric matricesJournal of Computational Physics, 1975