The regularized method of analytic continuation is used to study the low-energy negative-ion states of

beryllium (configuration 2s2εp 2P ) and magnesium (configuration 3s2εp 2P ) atoms. The method applies an

additional perturbation potential and requires only routine bound-state multi-electron quantum calculations. Such

computations are accessible by most of the free or commercial quantum chemistry software available for atoms

and molecules. The perturbation potential is implemented as a spherical Gaussian function with a fixed width.

Stability of the analytic continuation technique with respect to the width and with respect to the input range of

electron affinities is studied in detail. The computed resonance parameters Er = 0.282 eV, = 0.316 eV for the

2p state of Be− and Er = 0.188 eV, = 0.167 for the 3p state of Mg− agree well with the best results obtained

by much more elaborate and computationally demanding present-day methods

beryllium (configuration 2s2εp 2P ) and magnesium (configuration 3s2εp 2P ) atoms. The method applies an

additional perturbation potential and requires only routine bound-state multi-electron quantum calculations. Such

computations are accessible by most of the free or commercial quantum chemistry software available for atoms

and molecules. The perturbation potential is implemented as a spherical Gaussian function with a fixed width.

Stability of the analytic continuation technique with respect to the width and with respect to the input range of

electron affinities is studied in detail. The computed resonance parameters Er = 0.282 eV, = 0.316 eV for the

2p state of Be− and Er = 0.188 eV, = 0.167 for the 3p state of Mg− agree well with the best results obtained

by much more elaborate and computationally demanding present-day methods

typ: | article |
---|---|

journal: | Physical Review A |

volume: | 97 |

pages: | 052704 |

year: | 2018 |