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DOE OSTI · 22095746

Three-body hyperspherical method with infinite angular expansions

Huili, Han·Liyan, Tang·Tingyun, Shi
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Abstract

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.

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74 ATOMIC AND MOLECULAR PHYSICSAPPROXIMATIONSCONFIGURATION INTERACTIONGROUND STATESHELIUMPOSITRONSSPLINE FUNCTIONSTESTINGTHREE-BODY PROBLEMWAVE FUNCTIONS

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Huili, Han, Liyan, Tang, Tingyun, Shi. 2011-12-15. Three-body hyperspherical method with infinite angular expansions. https://doi.org/10.1103/physreva.84.064503

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