Back to Search
Start Over
Computing vibrational energy levels by using mappings to fully exploit the structure of a pruned product basis.
- Source :
-
The Journal of chemical physics [J Chem Phys] 2009 Jun 07; Vol. 130 (21), pp. 214110. - Publication Year :
- 2009
-
Abstract
- For the purpose of calculating (ro-)vibrational spectra, rate constants, scattering cross sections, etc. product basis sets are very popular. They, however, have the important disadvantage that they are unusably large for systems with more than four atoms. In this paper we demonstrate that it is possible to efficiently use a basis set obtained by removing, from a product basis set, functions associated with the largest diagonal Hamiltonian matrix elements. This is done by exploiting the fact that for every factor of every term in the Hamiltonian, there is a basis-set order in which the matrix representation of the factor is block diagonal. Due to this block diagonality the Lanczos algorithm can be implemented efficiently. Tests with model Hamiltonians with as many as 32 coordinates illustrate the merit of the ideas.
Details
- Language :
- English
- ISSN :
- 1089-7690
- Volume :
- 130
- Issue :
- 21
- Database :
- MEDLINE
- Journal :
- The Journal of chemical physics
- Publication Type :
- Academic Journal
- Accession number :
- 19508059
- Full Text :
- https://doi.org/10.1063/1.3140272