The convergence of coupled-cluster equations for several cases, CCD, CCSD, CCSDT-n and the full CCSDT is investigated. Comparisons are made between the reduced linear equation (RLE) method for accelerating convergence and simple geometric extrapolation techniques, and between energy and wavefunction
The convergence of coupled-cluster methods for Be2
โ Scribed by William A. Shirley; G.A. Petersson
- Publisher
- Elsevier Science
- Year
- 1991
- Tongue
- English
- Weight
- 234 KB
- Volume
- 181
- Category
- Article
- ISSN
- 0009-2614
No coin nor oath required. For personal study only.
๐ SIMILAR VOLUMES
With the help of G. Scuseria and H.F. Schaefer III, we have found an improper factor of 2 in non-linear HN T: contributions to T, amplitudes only for the fill CCSDT results
The convergence of an iterative matrix-oriented coupled cluster approach is investigated and compared with a more recent implementation. Where the reference wavefunction dominates, the special features of the matrix-oriented implementation result in rapid convergence.
The direct mversion of the iterative subspace (DIIS) method is implemented into the closed-shell coupled-cluster single-and double-excitation (CCSD! model to improve the convergence of the coupled non-linear CCSD equations. As with self-consistent field and gradient methods the DIE method proves to
Two triple excitation equation-of-motion coupled-cluster (EOM-CC) methods for excitation energies are derived, implemented, and tested. They are excited state analogues of the CC singles, doubles, and linearized triples (CCSDT-1) iterative method and the CCSD method with a noniterative inclusion of