@article { ISI:000269926200012, title = {Intermediate hamiltonian hilbert space coupled cluster method: theory and pilot application}, journal = {International Journal of Quantum Chemistry}, volume = {109}, number = {13}, year = {2009}, month = {NOV}, pages = {2909-2915}, publisher = {JOHN WILEY \& SONS INC}, address = {111 RIVER ST, HOBOKEN, NJ 07030 USA}, abstract = {

The intermediate Hamiltonian state universal (Hilbert-space) coupled-cluster method is presented, using a formalism similar to that developed for the valence universal (Fock-space) approach. The method is expected to be applicable to many states not accessible by traditional multiroot multireference all-order size-extensive approaches. A pilot application to excited states of atomic beryllium shows good convergence and agreement with experiment and full CI values. (C) 2009 Wiley Periodicals, Inc. Int J Quantum Chem 109: 2909-2915, 2009

}, keywords = {coupled cluster, Hilbert space, intermediate Hamiltonian}, issn = {0020-7608}, doi = {10.1002/qua.22155}, author = {Eliav, Ephraim and Borschevsky, Anastasia and Shamasundar, K. R. and Pal, Sourav and Kaldor, Uzi} }