New theoretical approach for autoionizing states

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1988

OSTI ID:5912779

Seminario, J M

An adaptation of the Feschbach Projection Operator Formalism to Z-dependent Perturbation Theory has been carried out for the calculation of autoionizing states of two electron systems under the configuration 2s2p. This analogue of the Feshbach projection method in Z-dependent perturbation theory produces results to higher order for the eigenvalues of the projected hamiltonian of two-electron atoms. This new way of calculating autoionizing states, takes advantage of the best features of both techniques to get more precise and more reliable results than any other calculation. It is shown in perturbation theory that the Feshbach projection procedure for multielectron systems can be carried out without the need for the exact wave function of the target state. Instead, only the zero-order wave function of the target is required. For three electron atoms, the first order wave function is the sum of appropriate first order, two-electron wave functions. Therefore low-order results for resonance states of three electron ions are easily obtained. The attempt to use this technique in three-electron systems results in surprising agreement with other calculations for the different states associated to the 1s2s2p configuration. Results have been compared with experiments whenever the corresponding experiments have been performed, obtaining excellent agreement.

• Research Organization: Southern Illinois Univ., Carbondale, IL (USA)
• OSTI ID: 5912779
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
ATOMS
AUTOIONIZATION
COMPARATIVE EVALUATIONS
DATA
EIGENVALUES
ELECTRONIC STRUCTURE
ENERGY LEVELS
FUNCTIONS
HAMILTONIANS
INFORMATION
IONIZATION
MATHEMATICAL OPERATORS
NUMERICAL DATA
PERTURBATION THEORY
QUANTUM OPERATORS
THEORETICAL DATA
WAVE FUNCTIONS