Abstract
The Rayleigh-Schrodinger perturbation formalism is extended to the case of a model space, which is not necessarily degenerate. The model space defines the zero-order or model wavefunction, and the new formalism makes it possible to use a model wavefunction of multi-configurational type. The effect of the states outside the model space are taken into account by means of a perturbation expansion and expressed in terms of an 'effective' Hamiltonian, operating only within the model space. The extended Rayleigh Schrodinger formalism is used to prove the linked-diagram theorem for a multi-configurational model space in a simple way. The problem of convergence of the perturbation expansion is briefly discussed.
Keywords
Degenerate energy levelsHamiltonian (control theory)Wave functionPerturbation (astronomy)Schrödinger's catMathematical physicsConfiguration spacePhysicsFormalism (music)MathematicsSchrödinger equationQuantum mechanicsClassical mechanics
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Publication Info
- Year
- 1974
- Type
- article
- Volume
- 7
- Issue
- 18
- Pages
- 2441-2470
- Citations
- 449
- Access
- Closed
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Cite This
Ingvar Lindgren
(1974).
The Rayleigh-Schrodinger perturbation and the linked-diagram theorem for a multi-configurational model space.
Journal of Physics B Atomic and Molecular Physics
, 7
(18)
, 2441-2470.
https://doi.org/10.1088/0022-3700/7/18/010
Identifiers
- DOI
- 10.1088/0022-3700/7/18/010