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Title: Ionization potential of {sup 9}Be calculated including nuclear motion and relativistic corrections

Abstract

Variational calculations employing explicitly correlated Gaussian functions have been performed for the ground states of {sup 9}Be and {sup 9}Be{sup +} including the nuclear motion [i.e., without assuming the Born-Oppenheimer (BO) approximation]. An approach based on the analytical energy gradient calculated with respect to the Gaussian exponential parameters was employed, leading to energies of the two systems noticeably improved over those found in the recent paper of Pachucki and Komasa [Phys. Rev. A 73, 052502 (2006)]. The non-BO wave functions were used to calculate the {alpha}{sup 2} relativistic corrections ({alpha}=e{sup 2}/({Dirac_h}/2{pi})c). With those corrections and the {alpha}{sup 3} and {alpha}{sup 4} corrections taken from Pachucki and Komasa, a new value of the ionization potential (IP) of {sup 9}Be was determined. It agrees very well with the most recent experimental IP.

Authors:
 [1];  [2];  [3];  [1];  [1];  [4]
  1. Department of Chemistry, University of Arizona, Tucson, Arizona 85721 (United States)
  2. (Poland)
  3. Department of Chemistry, Nicholas Copernicus University, ulica Gagarina 7, PL 87-100 Torun (Poland)
  4. (United States)
Publication Date:
OSTI Identifier:
20982518
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevA.75.052510; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; BERYLLIUM 9; BERYLLIUM IONS; BORN-OPPENHEIMER APPROXIMATION; COMPUTER CALCULATIONS; CORRECTIONS; GAUSS FUNCTION; GAUSSIAN PROCESSES; GROUND STATES; IONIZATION POTENTIAL; RELATIVISTIC RANGE; VARIATIONAL METHODS; WAVE FUNCTIONS

Citation Formats

Stanke, Monika, Institute of Physics, Nicholas Copernicus University, ulica Grudziadzka 5, PL 87-100 Torun, Kedziera, Dariusz, Bubin, Sergiy, Adamowicz, Ludwik, and Department of Physics, University of Arizona, Tucson, Arizona 85721. Ionization potential of {sup 9}Be calculated including nuclear motion and relativistic corrections. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.052510.
Stanke, Monika, Institute of Physics, Nicholas Copernicus University, ulica Grudziadzka 5, PL 87-100 Torun, Kedziera, Dariusz, Bubin, Sergiy, Adamowicz, Ludwik, & Department of Physics, University of Arizona, Tucson, Arizona 85721. Ionization potential of {sup 9}Be calculated including nuclear motion and relativistic corrections. United States. doi:10.1103/PHYSREVA.75.052510.
Stanke, Monika, Institute of Physics, Nicholas Copernicus University, ulica Grudziadzka 5, PL 87-100 Torun, Kedziera, Dariusz, Bubin, Sergiy, Adamowicz, Ludwik, and Department of Physics, University of Arizona, Tucson, Arizona 85721. Tue . "Ionization potential of {sup 9}Be calculated including nuclear motion and relativistic corrections". United States. doi:10.1103/PHYSREVA.75.052510.
@article{osti_20982518,
title = {Ionization potential of {sup 9}Be calculated including nuclear motion and relativistic corrections},
author = {Stanke, Monika and Institute of Physics, Nicholas Copernicus University, ulica Grudziadzka 5, PL 87-100 Torun and Kedziera, Dariusz and Bubin, Sergiy and Adamowicz, Ludwik and Department of Physics, University of Arizona, Tucson, Arizona 85721},
abstractNote = {Variational calculations employing explicitly correlated Gaussian functions have been performed for the ground states of {sup 9}Be and {sup 9}Be{sup +} including the nuclear motion [i.e., without assuming the Born-Oppenheimer (BO) approximation]. An approach based on the analytical energy gradient calculated with respect to the Gaussian exponential parameters was employed, leading to energies of the two systems noticeably improved over those found in the recent paper of Pachucki and Komasa [Phys. Rev. A 73, 052502 (2006)]. The non-BO wave functions were used to calculate the {alpha}{sup 2} relativistic corrections ({alpha}=e{sup 2}/({Dirac_h}/2{pi})c). With those corrections and the {alpha}{sup 3} and {alpha}{sup 4} corrections taken from Pachucki and Komasa, a new value of the ionization potential (IP) of {sup 9}Be was determined. It agrees very well with the most recent experimental IP.},
doi = {10.1103/PHYSREVA.75.052510},
journal = {Physical Review. A},
number = 5,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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