2000/01/25 by V. A. Dzuba, V. V. Flambaum, C. Harabati · 1 citation
Engineering · Physics and Astronomy · #Advanced Chemical Physics Studies #Atomic and Molecular Physics #Muon and positron interactions and applications #physics.atom-ph
paper · pdf · doi:10.1103/physreva.62.042504
15 pages; LaTeX; Submitted to Phys. Rev. A
arxiv created 2000/01/25 · openalex publication_date 2000/09/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Positron binding to silver and gold atoms was studied using a fully ab initio relativistic method, which combines the configuration-interaction method with many-body perturbation theory. It was found that the silver atom forms a bound state with a positron with binding energy 123 (\ifmmode±\else\textpm\fi30%) meV, while the gold atom cannot bind a positron. Our calculations reveal the importance of the relativistic effects for positron binding to heavy atoms. The role of these effects was studied by varying the value of the fine-structure constant \ensuremathα. In the nonrelativistic limit, \ensuremathα=0, both systems e+Ag and e+Au are bound with binding energies of about 200 meV for e+Ag and 220 meV for e+Au. Relativistic corrections for a negative ion are essentially different from that for a positron interacting with an atom. Therefore the calculation of electron affinities cannot serve as a test of the method used for positron binding in the nonrelativistic case. However, it is still a good test of the relativistic calculations. Our calculated electron affinities for silver (1.327 eV) and gold (2.307 eV) atoms are in very good agreement with corresponding experimental values (1.303 and 2.309 eV, respectively).