Shape resonances of Be$^-$ and Mg$^-$ investigated with method of analytic continuation

Bibliographic Details
Title: Shape resonances of Be$^-$ and Mg$^-$ investigated with method of analytic continuation
Authors: Čurík, Roman, Paidarová, Ivana, Horáček, Jiří
Source: Phys. Rev. A 97, 052704 (2018)
Publication Year: 2018
Collection: Physics (Other)
Subject Terms: Physics - Chemical Physics
More Details: The regularized method of analytic continuation is used to study the low-energy negative ion states of beryllium (configuration 2$s^2\varepsilon p\; ^2P$) and magnesium (configuration 3$s^2\varepsilon p\; ^2P$) atoms. The method applies an additional perturbation potential and it 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 $E_r$=0.282 eV, $\Gamma$=0.316 eV for the $2p$ state of Be$^-$ and $E_r$=0.188 eV, $\Gamma$=0.167 for the $3p$ state of Mg$^-$, agree well with the best results obtained by much more elaborated and computationally demanding present-day methods.
Comment: 13 pages, 4 figures
Document Type: Working Paper
DOI: 10.1103/PhysRevA.97.052704
Access URL: http://arxiv.org/abs/1803.05178
Accession Number: edsarx.1803.05178
Database: arXiv
More Details
DOI:10.1103/PhysRevA.97.052704