We discuss conditions under which extended Koopmans' eigenvalues become exact ionisatlon potentials. Second-order perturbation theory is used to compare with known expressions involving relaxation contributions to the exact resulls. In two-electron systems all the EK elgenvalues are shown to be exac
On the extended eigenvalues and extended eigenvectors of shift operator on the Wiener algebra
✍ Scribed by M. Gürdal
- Publisher
- Elsevier Science
- Year
- 2009
- Tongue
- English
- Weight
- 277 KB
- Volume
- 22
- Category
- Article
- ISSN
- 0893-9659
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✦ Synopsis
In the present paper we consider the shift operator S on the Wiener algebra W (D) of analytic functions on the unit disc D of the complex plane C. A complex number λ is called an extended eigenvalue of S if there exists a nonzero operator A satisfying the equation AS = λSA. We prove that the set of all extended eigenvalues of S is precisely the set D, and describe in terms of multiplication operators and composition operators the set of all corresponding extended eigenvectors of S.
📜 SIMILAR VOLUMES
The wave function of a system may be expanded in terms of eigenfunctions of the N -1 electron Hamiltonian times one-particle functions known as generalized overlap amplitudes (GOAS). The one-electron operator whose eigenfunctions are the GOAS is presented, without using an energy-dependent term as i