Abstract
The converged accurate quantal rovibrational partition functions for a polyatomic molecule with a torsion are discussed. The study was carried out by the TT-FPI-ESPE path-integral method, and the statistical errors in the free energies are about 0.1% from 400 to 2400k. The free energy values obtained from the path-integral calculation were compared to separable-mode approximation and to value in thermodynamic tables. The results allow, for the first time, to test the effect of anharmonicity and vibrational-rotational coupling for a molecule with a torsion.
Original language | English (US) |
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Pages (from-to) | 5148-5162 |
Number of pages | 15 |
Journal | Journal of Chemical Physics |
Volume | 121 |
Issue number | 11 |
DOIs | |
State | Published - Sep 15 2004 |