The calculation of the ground state energy of weakly bound van der waals trimers using the method of hyperspherical harmonics.: II. Non-adiabatic corrections

doi:10.1016/0301-0104(85)80183-X

Chemical Physics

Volume 99, Issue 3, 1 November 1985, Pages 427-435

https://doi.org/10.1016/0301-0104(85)80183-X Get rights and content

Abstract

Accurate calculations of the ground state energy levels of the three-particle van der Waals complexes Ne₃ and (H₂)₃ are presented. The method uses a hyperspherical coordinate system and is based on a Born-Oppenheimer separation of the hyper-radial and angular degrees of freedom. Non-adiabatic effects are included by Ryleigh-Schrödinger perturbation theory. A new accurate method based on Brillouin-Wigner perturbation theory is also presented.

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¹: Present address: Department of Chemistry, University of Southampton, Southampton SO9 5NH, UK.

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The calculation of the ground state energy of weakly bound van der waals trimers using the method of hyperspherical harmonics.: II. Non-adiabatic corrections

Abstract

Chem. Phys.

Mol. Phys.