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Tingyun, Shi

Publications and source records attributed to Tingyun, Shi.

3 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2011

Three-body hyperspherical method with infinite angular expansions

The hyperspherical method based on infinite angular expansions is introduced. We approximate the cusp behavior of a wave function using B-spline techniques. Calculations for the ground-state energies of the atomic helium and the e{sup +}Li system are presented as two examples for testing this method. The computed ground-state energy of He is -2.903 724 a.u. with single particle orbitals l{sub max}=8. For the e{sup +}Li system, with l{sub max}=9, the ground-state energy is -0.250 83 a.u., which is better than the configuration interaction result of -0.250 107 82 a.u. with l{sub max}=30.

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2011

Third-order perturbation theory for van der Waals interaction coefficients

The third-order expression for the dispersion interaction between two atoms is written as a sum over lists of transition matrix elements. Particular attention is given to the C{sub 9}/R{sup 9} interaction which occurs in the homonuclear case when one atom is in an S state and the other is in a P state. Numerical values of the C{sub 9} coefficient are given for the homonuclear alkali-metal dimers. The size of the C{sub 9}:C{sub 3} dispersion coefficient ratio increases for the heavier alkali-metal atoms. The C{sub 11} and C{sub 13} coefficients between two helium atoms and lithium atoms in their ground states are also given.

74 ATOMIC AND MOLECULAR PHYSICS↗