TUNNELING SPLITTINGS FOR THE NOMINAL OO STRETCHING AND OTHER VIBRATIONS OF TROPOLONE ISOTOPOMERS OBSERVED IN THE LOW FREQUENCY INFRARED SPECTRUM
Loading...
Date
2007
Journal Title
Journal ISSN
Volume Title
Publisher
Ohio State University
Abstract
Fourier transform infrared spectra including resolved spectral doublets for many transitions are reported for gaseous tropolone(OH), tropolone(OD), and (18-O,18-O)tropolone(OH) in the 800 to $150 \wn$ spectral range. The known zero-point tunneling splitting values $\Delta_{0}$ = $0.974 \wn$ for tropolone(OH) (Tanaka et al.) and 0.$051 \wn$ for tropolone(OD) (Keske et al.) allow vibrational state-specific tunneling splittings $\Delta_{v}$ to be estimated for fundamentals including the three with the strongest OO stretching displacements [cf. for tropolone(OH) $\nub{13}$ = $435.22 \wn$ with $\Delta_{13}$ = $1.71 \wn$ = 1.76 $\Delta_{0}$, and for tropolone(OD) $\nub{13}$ = $429.631 \wn$ with $\Delta_{13}$ = $0.311 \wn$ = 6.10 $\Delta_{0}$]. In addition to revealing isotope-dependent $\Delta_{v}$ splittings the FTIR study demonstrates effects due to dynamic couplings and potential function anharmonicity. Vibrational reassignments are fostered and the pattern of $\Delta_{v}$ tunneling splitting values is interpreted to underscore the intrinsic multidimensionality of the tautomerization process in this nonrigid 15 atom molecule.
Description
Author Institution: Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409}; Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA 99352