Journal
MOLECULAR PHYSICS
Volume 112, Issue 18, Pages 2462-2467Publisher
TAYLOR & FRANCIS LTD
DOI: 10.1080/00268976.2014.921341
Keywords
Eckart-Watson Hamiltonian; variational-perturbational approach; nuclear motion theory; C2H4; C2D4; CH4
Funding
- Hungarian Scientific Research Fund, OTKA [NK83583]
Ask authors/readers for more resources
A hybrid variational-perturbational nuclear motion algorithm based on the perturbative treatment of the Coriolis coupling terms of the Eckart-Watson kinetic energy operator following a variational treatment of the rest of the operator is described. The algorithm has been implemented in the quantum chemical code DEWE. Performance of the hybrid treatment is assessed by comparing selected numerically exact variational vibration-only and rovibrational energy levels of the C2H4, C2D4, and CH4 molecules with their perturbatively corrected counterparts. For many of the rotational-vibrational states examined, numerical tests reveal excellent agreement between the variational and even the first-order perturbative energy levels, whilst the perturbative approach is able to reduce the computational cost of the matrix-vector product evaluations, needed by the iterative Lanczos eigensolver, by almost an order of magnitude.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available