Variational calculation of specific, highly excited vibrational states in DFCO: comparison with experimental data.
A stimulated emission pumping spectra of jet-cooled DFCO performed by Crane et al. (J. Mol. Spectrosc. 1997, 183, 273) has provided a great number of ro-vibrational lines up to 9000 cm(-1) of excitation energy. By combining a Jacobi-Wilson (JW) approach with a Davidson scheme, we calculate the lines provided by the experiment up to 9000 cm(-1) using an ab initio global potential energy surface (PES) developed by Kato et al. (J. Chem. Phys. 1997, 107, 6114). Comparisons between experimental and calculated data provide a critical test of the quality of the PES used. We show that the variational calculated energies can be efficiently corrected by taking into account the error observed for the A' fundamental transitions nu(i) (i = 1, ..., 5) and the first overtone 2nu(6). A detailed analysis of the eigenstates obtained by the calculation allows one to quantify the coupling between the different modes. Such an information is essential to understand and predict the energy flow through a DFCO molecule that is initially excited.
Iung
Christophe
C
Equipe de Chimie Théorique, Méthodologies et Modélisation, Institut Gerhardt, UMR 5253 CNRS-UMII-ENSCM, CC 014, Université Montpellier II 34095 Montpellier Cedex 05, France. iung@univ-montp2.fr
Pasin
Gauthier
G