Effective Rotation-Pseudorotation Hamiltonian for X3-Type Molecules in the High-Barrier Limit

✍ Scribed by N. Ohashi; M. Tsuura; J.T. Hougen

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 840 KB
• Volume: 173
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.1995.1221

✦ Synopsis

The rotation-pseudorotation problem in (X_{3})-type molecules has been treated group-theoretically for the high-barrier tunneling case. Explicit expressions for rotation-pseudorotation Hamiltonian matrix elements, which take into account the interaction of overall rotation with the rotation of principal axes accompanying pseudorotation motion and with the angular momentum generated by pseudorotation motion, have been derived using an (m)-fold extended group of the (G_{12}) permutation-inversion group. Illustrative pseudorotation tunneling splitting patterns have been derived by numerically diagonalizing the resulting Hamiltonian matrix for (J=5), using rotational constants appropriate for (\mathrm{Na}_{3}) in the (B) state, together with various sets of tunneling parameters. These tunneling splittings can be qualitatively understood using the concept of twofold energy level clusters in asymmetric rotor molecules. (C 1995 Academic Press. Inc.