Nonadiabatic selection rules for the photoabsorption of H sup minus and He

Journal Article · Sat Jun 01 04:00:00 EDT 1991 · Physical Review, A; (USA)

DOI:https://doi.org/10.1103/PhysRevA.43.5821· OSTI ID:5572224

Sadeghpour, H R ^[1]

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1. Joint Institute for Laboratory Astrophysics, Boulder, Colorado 80309-0440 (US)

The method of hyperspherical coordinates is used in obtaining very highly excited two-electron adiabatic potential curves up to the {ital n}=12 hydrogenic threshold. The present numerical effort exploits the analytic nature of the solutions to the Schroedinger equation at small and large distances to diagonalize the hyperspherical Hamiltonian in the combined basis set. Numerical deficiencies resulting from a linear dependency of the total nonorthogonal basis set are overcome in an automatic fashion. A high degree of diabaticity is observed which limits the channel interaction to within a select set of hyperspherical channels. The validity of this quasiconstant of motion as reported by H. R. Sadeghpour and C. H. Greene (SG) (Phys. Rev. Lett. 65, 313 (1990)) for H{sup {minus}} is investigated for the photoabsorption of He and higher-{ital z} members of the He isoelectronic sequence. A generalized two-electron Rydberg formula capable of predicting the positions of the dominant He (ridge and valley) resonances is given. A new feature of the very-highly-excited resonance structure for H{sup {minus}} and He (observed only recently by Domke {ital et} {ital al}., Phys. Rev. Lett. 66, 1306 (1991)) is discussed. Semiempirical multichannel-quantum-defect fits are also made to the photodetachment spectra of H{sup {minus}}, supporting the conclusions reached in SG.

• OSTI ID: 5572224
• Journal Information: Physical Review, A; (USA), Journal Name: Physical Review, A; (USA) Vol. 43:11; ISSN 1050-2947; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
ABSORPTION SPECTRA
ADIABATIC APPROXIMATION
ANIONS
ATOM COLLISIONS
CHARGED PARTICLES
COLLISIONS
ELECTROMAGNETIC RADIATION
ELECTRONIC STRUCTURE
ELEMENTS
ENERGY LEVELS
EXCITED STATES
FLUIDS
GASES
HELIUM
HYDROGEN IONS
HYDROGEN IONS 1 MINUS
ION COLLISIONS
IONS
MANY-BODY PROBLEM
NONMETALS
PHOTON COLLISIONS
PHOTON-ATOM COLLISIONS
PHOTON-ION COLLISIONS
RADIATIONS
RARE GASES
RESONANCE
SPECTRA
TWO-BODY PROBLEM