scholarly journals Self‐consistent intermediate Hamiltonians: A coupled cluster type formulation of the singles and doubles configuration interaction matrix dressing

1995 ◽  
Vol 103 (7) ◽  
pp. 2576-2588 ◽  
Author(s):  
I. Nebot‐Gil ◽  
J. Sánchez‐Marín ◽  
J. P. Malrieu ◽  
J. L. Heully ◽  
D. Maynau
Keyword(s):  
Configuration Interaction ◽  
Interaction Matrix ◽  
Coupled Cluster ◽  
Self Consistent ◽  
Cluster Type ◽  
Intermediate Hamiltonians

Coupled-pair theories and Davidson-type corrections for quasidegenerate states: The H4 model revisited

1988 ◽  
Vol 53 (9) ◽  
pp. 1919-1942 ◽  
Author(s):  
Josef Paldus ◽  
Paul E. S. Wormer ◽  
Marc Benard
Keyword(s):  
Electron Correlation ◽  
Model System ◽  
Coupled Cluster ◽  
Electron Model ◽  
Hydrogen Molecules ◽  
Double Zeta ◽  
Correlation Problem ◽  
Variational Approaches ◽  
Cluster Type ◽  
The Many

The performance of various variational and non-variational approaches to the many-electron correlation problem is examined for a simple four-electron model system consisting of two stretched hydrogen molecules in trapezoidal, rectangular and linear configurations, in which the degree of quasi-degeneracy can be continuously varied from a non-degenerate to an almost degenerate situation. In contrast to an earlier work (K. Jankowski and J. Paldus, Int. J. Quantum Chem. 18, 1243 (1980)) we employ a double-zeta plus polarization basis and examine both single reference and multireference configuration interaction and coupled-cluster-type approaches. The performance of various Davidson-type corrections is also investigated.

scholarly journals A feasible approach for automatically differentiable unitary coupled-cluster on quantum computers

2021 ◽  
Author(s):  
Jakob S. Kottmann ◽  
Abhinav Anand ◽  
Alán Aspuru-Guzik
Keyword(s):  
Coupled Cluster ◽  
Quantum Computers ◽  
Evaluation Procedures ◽  
Cluster Type

We develop computationally affordable and encoding independent gradient evaluation procedures for unitary coupled-cluster type operators, applicable on quantum computers.

A self-consistent quasidegenerate coupled-cluster theory

1999 ◽  
Vol 311 (5) ◽  
pp. 372-378 ◽  
Author(s):  
Mark R. Hoffmann ◽  
Yuriy G. Khait
Keyword(s):  
Coupled Cluster ◽  
Coupled Cluster Theory ◽  
Cluster Theory ◽  
Self Consistent
Sign in / Sign up

Export Citation Format

Share Document