Coupled cluster theory and its applications to molecular properties

elective monographs

It is assumed that students completed the quantum chemistry and mathematics courses at the Faculty of Chemistry UW or equivalent courses.

Classroom

After this lecture a student should acquire knowledge about coupled cluster theory and about its applications in quantum chemistry calculations

During the lecture the second quantization will be recapitulated, then the diagrammatic approach will be presented. Then the following issues will be addressed:

1) electron correlation energy in the coupled cluster approximation

(CCSD, CCSDT, more approximate ways to account for triples excitations);

2) LR-CC and EOM-CC methods for excited states (CCSD, CCn);

3) density matrices and molecular properties of the first order (like e.g. dipole moments) for the ground state and excited states;

4) molecular properties of higher order (like e.g. polarizabilities).

There will be discussed the problems of size-consistency, limits of applicability of the single-reference CC approach. Additionally, the relationship between Moeller-Plesset theory and CC theory will be analyzed.

Some numerical examples of it ab initio calculations will be shown, which were obtained with available quantum chemistry programs.

http://tiger.chem.uw.edu.pl/staff/tania/CC_mono.pdf (in Polish)

Molecular Electronic-Structure Theory, T. Helgaker, P. Joergensen, J. Olsen (selected chapters)

A student knows the new methods in the branch of coupled cluster theory, their possibilities and limitations.

A student is able to select the appropriate model within coupled cluster theory for a particular case.

exam, consisting of a written and oral parts

not applicable