The Screening Effect(Screened Coulomb Potential) in Long-Range van der Waals and Retardation Coefficients for H-Solid Surface Interaction

M. Jasim, Majid.; San,; K. Khalff, A

	The Screening Effect(Screened Coulomb Potential) in Long-Range van der Waals and Retardation Coefficients for H-Solid Surface Interaction
Journal of Basrah Researches (Sciences)
Article 1, Volume 34, Issue 4, 2008, Pages 17-29 PDF (0 K)
Authors
Majid. M. Jasim; ; a K. Khalff
Abstract
In this paper , we calculated the long – range van der Waals coefficient C3 for hydrogen atom interact with many solid surfaces (conductor , semiconductor and insulator ) , and we calculated the retardation coefficient f3(R) for these interactions, all of these calculations were achieved for atom with a single valence electron moving in a screened coulomb potential and for a different screening lengths D . Our study require to evaluate the radial wave functions numerically for hydrogen atom under the effect of the screening by using the static screened coulomb potential, and , we computed accurately the transition energies E for each value of screening length D .The computed wave functions inters in calculating of the dynamic dipole polarizability which is derived by using (KPS) method, and it is combined between the perturbation and variation methods . Finally, two variational constants in the variational function are calculated, this is lead to two values of the effective transition frequencies wi and two corresponding effective oscillator strengths zi .Our results are in a good agreement with other researchers with respect to the values of the van der Waals coefficient C3 at neglecting the effect of the screening (D=∞) .
Keywords
Screening; Screening Coulomb Potential; van der Waals Coefficient; Retardation Effects

Statistics Article View: 26 PDF Download: 17