%0 Journal Article %1 B008063M %A Lischka, Hans %A Shepard, Ron %A Pitzer, Russell M. %A Shavitt, Isaiah %A Dallos, Michal %A Muller, Thomas %A Szalay, Peter G. %A Seth, Michael %A Kedziora, Gary S. %A Yabushita, Satoshi %A Zhang, Zhiyong %D 2001 %I The Royal Society of Chemistry %J Phys. Chem. Chem. Phys. %K chemistry configuration interaction quantum review %N 5 %P 664-673 %R 10.1039/B008063M %T High-level multireference methods in the quantum-chemistry program system COLUMBUS: Analytic MR-CISD and MR-AQCC gradients and MR-AQCC-LRT for excited states, GUGA spin-orbit CI and parallel CI density %U http://dx.doi.org/10.1039/B008063M %V 3 %X Development of several new computational approaches within the framework of multi-reference ab initio molecular electronic structure methodology and their implementation in the COLUMBUS program system are reported. These new features are: calculation of the analytical MR-CI gradient for excited states based on state-averaged MCSCF orbitals, the extension of the MR-ACPF/AQCC methods to excited states in the framework of linear-response theory, spin–orbit CI for molecules containing heavy atoms and the development of a massively-parallel code for the computation of the one- and two-particle density matrix elements. Illustrative examples are given for each of these cases.

@article{B008063M, abstract = {Development of several new computational approaches within the framework of multi-reference ab initio molecular electronic structure methodology and their implementation in the COLUMBUS program system are reported. These new features are: calculation of the analytical MR-CI gradient for excited states based on state-averaged MCSCF orbitals, the extension of the MR-ACPF/AQCC methods to excited states in the framework of linear-response theory, spin–orbit CI for molecules containing heavy atoms and the development of a massively-parallel code for the computation of the one- and two-particle density matrix elements. Illustrative examples are given for each of these cases. }, added-at = {2011-09-26T15:40:14.000+0200}, author = {Lischka, Hans and Shepard, Ron and Pitzer, Russell M. and Shavitt, Isaiah and Dallos, Michal and Muller, Thomas and Szalay, Peter G. and Seth, Michael and Kedziora, Gary S. and Yabushita, Satoshi and Zhang, Zhiyong}, biburl = {https://www.bibsonomy.org/bibtex/24a45beff4bff23a3fb800c9832cf1274/drmatusek}, doi = {10.1039/B008063M}, interhash = {3ccbe4cac7c41689525f96eb01b0f289}, intrahash = {4a45beff4bff23a3fb800c9832cf1274}, journal = {Phys. Chem. Chem. Phys.}, keywords = {chemistry configuration interaction quantum review}, month = {January}, number = 5, pages = {664-673}, publisher = {The Royal Society of Chemistry}, timestamp = {2012-05-21T14:00:12.000+0200}, title = {High-level multireference methods in the quantum-chemistry program system COLUMBUS: Analytic MR-CISD and MR-AQCC gradients and MR-AQCC-LRT for excited states{,} GUGA spin-orbit CI and parallel CI density}, url = {http://dx.doi.org/10.1039/B008063M}, volume = 3, year = 2001 }