A novel method for accurate calculation of highly excited large amplitude motion vibrational states of triatomic molecules is presented, which employs three sets of Jacobi coordinates. The method is particularly well suited for D3h floppy systems, since it allows easy construction of basis sets which reflect the full S3 permutational symmetry of the three identical nuclei. This reduces the computational effort and leads to unambiguous symmetry assignment of the calculated levels. The application to H+ 3 has produced converged vibrational (J=0) levels up to ≈30000 cm-1 above the potential minimum; their energies are in excellent agreement with, or lower than, those from previous calculations.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry