The construction of a size-extensive intermediate Hamiltonian in a coupled-cluster framework

doi:10.1016/0009-2614(92)85761-X

Chemical Physics Letters

Volume 197, Issue 3, 11 September 1992, Pages 236-242

https://doi.org/10.1016/0009-2614(92)85761-X Get rights and content

Abstract

A size-extensive formulation for an intermediate Hamiltonian H_int, furnishing size-extensive energies for the main roots, is presented. The working model space, comprised of the main and intermediate space, is taken as complete. The starting point is a shifted Bloch equation derived by us, involving shift operators generated by the projector spanned by the intermediate eigenvectors of H_int. It is shown that a manifestly size-extensive H_int can be constructed in the coupled-cluster framework provided we choose the shift operator explicitly as additively separable and the associated intermediate wave operator R as multiplicatively separable.

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The construction of a size-extensive intermediate Hamiltonian in a coupled-cluster framework

Abstract

Nucl. Phys.

Chem. Phys. Letters

Chem. Phys. Letters

Chem. Phys. Letters

Intern. J. Quantum Chem. Symp.

Chem. Phys. Letters

Chem. Phys. Letters

J. Chem. Phys.

J. Chem. Phys.

Chem. Phys. Letters

Chem. Phys. Letters

Chem. Phys. Letters

Chem. Phys.

Theoret Chim. Acta

J. Phys. B

Advan. Chem. Phys.

Rev. Mod. Phys.

J. Phys. B

Mol. Phys.

Mol. Phys.

J. Chem. Phys.

Intern. J. Quantum Chem. Symp.