Para-ortho isomerization of H2+. Non-Born-Oppenheimer direct variational calculations with explicitly correlated all-particle Gaussian functions

Nikita Kirnosov, Keeper L. Sharkey, Ludwik Adamowicz

Research output: Contribution to journalArticle

Abstract

Direct variational calculations are performed for all bound rovibrational states of the H2+ ion corresponding to the ground and first excited rotational levels (the N = 0 and N = 1 states). The Born-Oppenheimer (BO) approximation is not assumed in the calculations and all-particle explicitly correlated Gaussian basis functions are used for the wave-function expansion. The exponential parameters of the Gaussians are optimized with the aid of analytically calculated energy gradient determined with respect to these parameters. The non-BO energies are used to determine the ortho-para nuclear-spin isomerization energies and the non-BO wave functions are used to determine the expectation values of the interparticle distances.

Original languageEnglish (US)
Pages (from-to)134-140
Number of pages7
JournalChemical Physics Letters
Volume621
DOIs
StatePublished - Feb 4 2015

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Wave functions
Isomerization
isomerization
Born approximation
wave functions
Born-Oppenheimer approximation
Ions
nuclear spin
energy
gradients
expansion
ions

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Physics and Astronomy(all)

Cite this

Para-ortho isomerization of H2+. Non-Born-Oppenheimer direct variational calculations with explicitly correlated all-particle Gaussian functions. / Kirnosov, Nikita; Sharkey, Keeper L.; Adamowicz, Ludwik.

In: Chemical Physics Letters, Vol. 621, 04.02.2015, p. 134-140.

Research output: Contribution to journalArticle

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