Variational description of the Helium trimer using correlated hyperspherycal harmonic basis functions

Paolo Barletta; Alejandro Kievsky

doi:10.1103/physreva.64.042514

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Variational description of the Helium trimer using correlated hyperspherycal harmonic basis functions

Paolo Barletta·Alejandro Kievsky

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Abstract

A variational wave function constructed with correlated Hyperspherical Harmonic functions is used to describe the Helium trimer. This system is known to have a deep bound state. In addition, different potential models predict the existence of a shallow excited state that has been identified as an Efimov state. Using the Rayleigh-Ritz variational principle the energies and wave functions of both bound states have been obtained by solving a generalized eigenvalue problem. The introduction of a suitable correlation factor reduces considerably the dimension of the basis needed to accurately describe the structure of the system. The most recent helium-helium interactions have been investigated.

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Paolo Barletta, Alejandro Kievsky. 2001-07-20. Variational description of the Helium trimer using correlated hyperspherycal harmonic basis functions. https://doi.org/10.1103/physreva.64.042514

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