Application of variational Monte Carlo method to the confined helium atom

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• 作者：Salah B Doma (1)
  Fatma N El-Gammal (2)
  
• 关键词：Variational Monte Carlo method ; Helium atom ; Compression effect ; 31.15.xt ; 02.70.Ss ; 83.50.Uv
• 刊名：Journal of Theoretical and Applied Physics
• 出版年：2012
• 出版时间：December 2012
• 年：2012
• 卷：6
• 期：1
• 全文大小：238KB
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• 作者单位：Salah B Doma (1)
  Fatma N El-Gammal (2)
  
  1. Mathematics Department, Faculty of Science, Alexandria University, Alexandria, Egypt
  2. Mathematics Department, Faculty of Science, Menoufiya University, Shibin El-Kom, Egypt
  
• ISSN：2251-7235

文摘

A new application of variational Monte Carlo method is presented to study the helium atom under the compression effect of a spherical box with radius (r c ). The ground-state energies of the helium atom were calculated for different values of r c . Our calculations were extended to include Li+ and Be2+ ions. The calculations were based on the use of a compact accurate trial wave function with five variational parameters. To optimize variational parameters, we used the steepest descent method. The obtained results are in good agreement with previous results.