Is coupled cluster singles and doubles (CCSD) more computationally intensive than quadratic configuration interaction (QCISD)

It is shown that the recently proposed QCI method including all single and double substitutions has essentially the same computational requirements as the more complete CCSD approach. If properly formulated, the CCSD equations contain at most quadratic terms in the excitation amplitudes.

[1]  Josef Paldus,et al.  Correlation Problems in Atomic and Molecular Systems. IV. Extended Coupled-Pair Many-Electron Theory and Its Application to the B H 3 Molecule , 1972 .

[2]  J. S. Binkley,et al.  Electron correlation theories and their application to the study of simple reaction potential surfaces , 1978 .

[3]  R. Bartlett.  Many-Body Perturbation Theory and Coupled Cluster Theory for Electron Correlation in Molecules , 1981 .

[4]  Rodney J. Bartlett,et al.  The reduced linear equation method in coupled cluster theory. , 1981 .

[5]  Peter Pulay,et al.  An efficient reformulation of the closed‐shell self‐consistent electron pair theory , 1984 .

[6]  Henry F. Schaefer,et al.  Accelerating the convergence of the coupled-cluster approach: The use of the DIIS method , 1986 .

[7]  Peter Pulay,et al.  Fourth‐order Mo/ller–Plessett perturbation theory in the local correlation treatment. I. Method , 1987 .

[8]  Martin Head-Gordon,et al.  Quadratic configuration interaction. A general technique for determining electron correlation energies , 1987 .

[9]  Julia E. Rice,et al.  The closed‐shell coupled cluster single and double excitation (CCSD) model for the description of electron correlation. A comparison with configuration interaction (CISD) results , 1987 .

[10]  Julia E. Rice,et al.  Analytic evaluation of energy gradients for the single and double excitation coupled cluster (CCSD) wave function: Theory and application , 1987 .

[11]  D. Cremer,et al.  Analytical evaluation of energy gradients in quadratic configuration interaction theory , 1988 .

[12]  Curtis L. Janssen,et al.  An efficient reformulation of the closed‐shell coupled cluster single and double excitation (CCSD) equations , 1988 .

[13]  W. D. Allen,et al.  The anharmonic force fields of HOF and F2O , 1988 .

[14]  R. Bartlett,et al.  A study of the Be2 potential curve using the full (CCSDT) coupled‐cluster method: The importance of T4 clusters , 1988 .