Configuration-interaction calculation of the Cue(+) ground state

Citation
J. Mitroy et G. Ryzhikh, Configuration-interaction calculation of the Cue(+) ground state, J PHYS B, 32(12), 1999, pp. 2831-2839
Citations number
30
Categorie Soggetti
Physics
Journal title
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
ISSN journal
09534075 → ACNP
Volume
32
Issue
12
Year of publication
1999
Pages
2831 - 2839
Database
ISI
SICI code
0953-4075(19990628)32:12<2831:CCOTCG>2.0.ZU;2-M
Abstract
A configuration-interaction (CI) calculation has confirmed an earlier predi ction of positron binding to neutral copper. The single-centre CI expansion gave a binding energy of 0.003 69 Hartree and a 2 gamma annihilation rate of 0.246 x 10(9) s(-1) The energy and annihilation rate are different from a previous calculation using the fixed-core stochastic variational method ( FCSVM) due to the slow convergence of the CI calculation with respect to th e number of spherical harmonics included in the CI expansion. An extrapolat ion of the CI calculation to the infinite spherical harmonic limit improves the quality of agreement with the earlier FCSVM calculation. The present c alculation highlights the importance of an explicit treatment of the strong electron-positron correlations which are present when positrons interact w ith atoms.