A completely general formalism is developed to describe the energy E disp ? ?sCs/Rs of dispersion interaction between two atoms in spherically symmetric states. Explicit expressions are given up to the tenth order of perturbation theory for the dispersion energy Edisp and dispersion coefficients Cs. The method could, in principle, be used to derive the expressions for any s while including all contributing orders of perturbation theory for asymptotic interaction between two atoms. The theory is applied to the calculation of the complete series up to s ? 30 for two hydrogen atoms in their ground state. A pseudo-state series expansion of the two-atom Green function gives rapid convergence of the series for radial matrix elements. The numerical values of Cs are computed up to C30 to a relative accuracy of 10-7 or better. The dispersion coefficients for the hydrogen-antihydrogen interaction are obtained from the H-H coefficients by simply taking the absolute magnitude of Cs. � 2006 IOP Publishing Ltd.
|Number of pages||29|
|Journal||Journal of Physics B: Atomic, Molecular and Optical Physics|
|Publication status||Published - 2006|