Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2007-07-20
Physics
Condensed Matter
Strongly Correlated Electrons
16 pages, 7 figures, to be published in J. Chem. Phys
Scientific paper
10.1063/1.2761870
The Canonical Transformation theory of Yanai and Chan [J. Chem. Phys. 124, 194106 (2006)] provides a rigorously size-extensive description of dynamical correlation in multireference problems. Here we describe a new formulation of the theory based on the extended normal ordering procedure of Mukherjee and Kutzelnigg [J. Chem. Phys. 107, 432 (1997)]. On studies of the water, nitrogen, and iron-oxide potential energy curves, the Linearised Canonical Transformation Singles and Doubles theory is competitive in accuracy with some of the best multireference methods, such as the Multireference Averaged Coupled Pair Functional, while computational timings (in the case of the iron-oxide molecule) are two-three orders of magnitude faster and comparable to those of Complete Active Space Second-Order Perturbation Theory. The results presented here are greatly improved both in accuracy and in cost over our earlier study as the result of a new numerical algorithm for solving the amplitude equations.
Chan Garnet Kin-Lic
Yanai Takeshi
No associations
LandOfFree
A canonical transformation theory from extended normal ordering does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A canonical transformation theory from extended normal ordering, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A canonical transformation theory from extended normal ordering will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-399336