### Abstract

Direct variational calculations are performed for all bound rovibrational states of the H_{2}^{+} 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 language | English (US) |
---|---|

Pages (from-to) | 134-140 |

Number of pages | 7 |

Journal | Chemical Physics Letters |

Volume | 621 |

DOIs | |

State | Published - Feb 4 2015 |

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### ASJC Scopus subject areas

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

### Cite this

**Para-ortho isomerization of H _{2}^{+}. Non-Born-Oppenheimer direct variational calculations with explicitly correlated all-particle Gaussian functions.** / Kirnosov, Nikita; Sharkey, Keeper L.; Adamowicz, Ludwik.

Research output: Contribution to journal › Article

_{2}

^{+}. Non-Born-Oppenheimer direct variational calculations with explicitly correlated all-particle Gaussian functions',

*Chemical Physics Letters*, vol. 621, pp. 134-140. https://doi.org/10.1016/j.cplett.2014.12.060

}

TY - JOUR

T1 - Para-ortho isomerization of H2+. Non-Born-Oppenheimer direct variational calculations with explicitly correlated all-particle Gaussian functions

AU - Kirnosov, Nikita

AU - Sharkey, Keeper L.

AU - Adamowicz, Ludwik

PY - 2015/2/4

Y1 - 2015/2/4

N2 - 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.

AB - 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.

UR - http://www.scopus.com/inward/record.url?scp=84921047811&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84921047811&partnerID=8YFLogxK

U2 - 10.1016/j.cplett.2014.12.060

DO - 10.1016/j.cplett.2014.12.060

M3 - Article

AN - SCOPUS:84921047811

VL - 621

SP - 134

EP - 140

JO - Chemical Physics Letters

JF - Chemical Physics Letters

SN - 0009-2614

ER -