Journal Article10.1103/PHYSREVA.44.232
Photoionization of two-electron atoms using a nonvariational configuration-interaction approach with discretized finite basis
T. N. Chang,X. Tang +1 more
85
TL;DR: The excellent agreement between the present calculation and other existing theoretical and experimental results, in addition to the extensive recent applications of this procedure to the bound excited states of divalent atoms, has further demonstrated the effectiveness of this simple configuration-interaction procedure.
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Abstract: We present an extension of a simple configuration-interaction procedure to the photoionization of two-electron atoms. By using a finite basis set constructed from {ital B} splines, this nonvariational approach does not rely on any optimum procedure, which is often required in other more elaborate configuration-interaction calculations. The quantitative accuracy of this procedure is tested by examining the photoionization cross sections at photon energies immediately above the first ionization threshold, as well as near the doubly excited 2{ital s}2{ital p} {sup 1}{ital P} resonance structure. The {ital S}- and {ital P}-wave phase shifts for the electron-hydrogen scattering calculated with this procedure are also presented. The excellent agreement between the present calculation and other existing theoretical and experimental results, in addition to the extensive recent applications of this procedure to the bound excited states of divalent atoms, has further demonstrated the effectiveness of this simple configuration-interaction procedure.
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Citations
Application of B-splines to determining eigen-spectrum of Feshbach molecules
TL;DR: In this paper, the B-spline basis set method is applied to determining the rovibrational eigenspectrum of diatomic molecules and a particular attention is paid to a challenging numerical task of an accurate and efficient description of the vibrational levels near the dissociation limit (halo-state and Feshbach molecules).
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Wavelength dependence of the nonresonant photoionization cross section of a two-electron atom near the ionization threshold.
T. N. Chang,T.K. Fang +1 more
TL;DR: It is shown that in the absence of a strongly energy-dependent feature such as a doubly excited resonance, the photoionization cross sections in the immediate vicinity of the ionization threshold depend {ital linearly} on the wavelengths of the incident light.
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Spline-Galerkin methods for Rydberg series, including Breit-Pauli effects
TL;DR: In this article, the spline-Galerkin method for Rydberg series of atomic systems is extended to Breit-Pauli configuration interaction calculations, and the resulting energies agree very well with recent experiments.
14
Time-resolved resonant photoionization of He using a time-dependent Feshbach method with ultrashort laser pulses
TL;DR: In this paper, the authors studied the photoionization and autoionization of the helium atom subject to ultrashort laser pulses by using a Feshbach formalism in the time domain.
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Sub-nanohartree accuracy from LCAO expansion with B-spline functions. An application to H+2 and HeH2+
TL;DR: The one-centre variational algorithm successfully applied to H+2 and HeH2+ discrete and continuum states calculation is extended according to an LCAO-type expansion approach with the B-spline basis sub-nanohartree accuracy reached.
14
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