Theory and computation of triply excited resonances: Application to states of He[sup [minus]]

Journal Article · Mon Nov 01 04:00:00 EST 1993 · Physical Review A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.48.3578· OSTI ID:5922980

Nicolaides, C A; Piangos, N A; Komninos, Y ^[1]

---

1. Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens (Greece)

Autoionizing multiply excited states offer unusual challenges to the theory of electronic structure and spectra because of the presence of strong electron correlations, of their occasional weak binding, of their proximity to more than one threshold, and of their degeneracy with many continua. Here we discuss a theory that addresses these difficulties in conjunction with the computation of their wave functions and intrinsic properties. Emphasis is given on the justification of the possible presence of self-consistently obtained open-channel-like (OCL) correlating configurations in the square-integrable representation of such states and on their effect on the energy [ital E] and the width [Gamma]. Application of the theory has allowed the prediction of two hitherto unknown He[sup [minus]] triply excited resonances, the 2[ital s]2[ital p][sup 2] [sup 2][ital P] ([ital E]=59.71 eV, above the He ground state, [Gamma]=79 meV) and the 2[ital p][sup 3] [sup 2][ital D[ital o]] ([ital E]=59.46 eV, [Gamma]=282 meV) (1 a.u.=27.2116 eV). These resonances are above the singly excited states of He and are embedded in its doubly excited spectrum. The relatively broad 2[ital p][sup 3] [sup 2][ital D[ital o]] state interacts strongly with the He 2[ital s]2[ital p] [sup 3][ital P[ital o]] [epsilon][ital d] continuum. The effect of this interaction has been studied in terms of the coupling with fixed core scattering states as well as with a self-consistently computed OCL bound configuration.

• OSTI ID: 5922980
• Journal Information: Physical Review A; (United States), Journal Name: Physical Review A; (United States) Vol. 48:5; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

664100* -- Theory of Electronic Structure of Atoms & Molecules-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ANIONS
AUTOIONIZATION
CHARGE STATES
CHARGED PARTICLES
CLASSIFICATION
CONFIGURATION
ENERGY LEVELS
EXCITED STATES
HELIUM IONS
IONIZATION
IONS
RESONANCE