The higher order C_n dispersion coefficients for the alkali atoms
arXiv:physics/0411174 · doi:10.1103/PhysRevA.71.042701
Abstract
The van der Waals coefficients, from C_11 through to C_16 resulting from 2nd, 3rd and 4th order perturbation theory are estimated for the alkali (Li, Na, K and Rb) atoms. The dispersion coefficients are also computed for all possible combinations of the alkali atoms and hydrogen. The parameters are determined from sum-rules after diagonalizing the fixed core Hamiltonian in a large basis. Comparisons of the radial dependence of the C_n/r^n potentials give guidance as to the radial regions in which the various higher-order terms can be neglected. It is seen that including terms up to C_10/r^10 results in a dispersion interaction that is accurate to better than 1 percent whenever the inter-nuclear spacing is larger than 20 a_0. This level of accuracy is mainly achieved due to the fortuitous cancellation between the repulsive (C_11, C_13, C_15) and attractive (C_12, C_14, C_16) dispersion forces.
8 pages, 7 figures
References in corpus (9)
- Inter-isotope determination of ultracold rubidium interactions from three high-precision experiments
- High-precision calculations of dispersion coefficients, static dipole polarizabilities, and atom-wall interaction constants for alkali-metal atoms
- High-precision calculations of van der Waals coefficients for heteronuclear alkali-metal dimers
- Accurate relativistic many-body calculations of van der Waals coefficients C_8 and C_10 for alkali-metal dimers
- High-accuracy relativistic many-body calculations of van der Waals coefficients C_6 for alkaline-earth atoms
- Experimental study of the Ca2 1S+1S asymptote
- Scattering length of the ground state Mg+Mg collision
- Calculation of the interspecies s-wave scattering length in an ultracold Na-Rb vapor
- The higher-order C_n dispersion coefficients for hydrogen