## Abstract

Converged full-dimensional (6D) quantum mechanical calculation of energy levels of intramolecular stretching excited (HF)_{2}(v_{1}v _{2}) is presented for (v_{1}v_{2}) = (01), (10), (02), (20), and (11). The bound state calculation for the excited HF dimer employs the SQSBDE potential energy surface of Quack and Suhm and is for total angular momentum J = 0. This calculation provides the first rigorous theoretical result of energy levels for HF stretching excited HF dimer in full dimensions. The calculated fundamental transition frequencies are v_{1} = 3940.6 cm ^{-1} and v_{2} = 3896.4 cm^{-1}. These values are somewhat larger than the corresponding experimental measurement of 3930.9 cm^{-1} for v_{1} and 3868.3 cm^{-1} for v_{2}. The overtone frequencies are calculated to be 2v_{1} = 7713.5 cm ^{-1}, 2v_{2} = 7642.5 cm^{-1}, and v_{1} + v_{2} = 7841.8 cm^{-1}. The theoretical tunneling splittings of the fundamentals v_{2} and v_{1} are, respectively, a factor of 5.3 and 3.7 smaller than the ground state splitting, compared to a factor of 3 from the experimental measurement. The splittings of the overtone states 2v _{2}, 2v_{1}, and v_{1} + v_{2} are smaller than that of the ground state by factors of 9.6, 48, and 1.8, respectively. Some of the calculated energy levels of excited (HF)_{2} are spectroscopically characterized and assigned.

Original language | English (US) |
---|---|

Pages (from-to) | 2548-2554 |

Number of pages | 7 |

Journal | The Journal of Chemical Physics |

Volume | 103 |

Issue number | 7 |

DOIs | |

State | Published - 1995 |

## ASJC Scopus subject areas

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