1. ANALYSIS OF ROTATIONAL STRUCTURE IN THE HIGH-RESOLUTION INFRARED SPECTRUM OF CIS,CIS-1,4-DIFLUOROBUTADIENE
NORMAN C. CRAIG and MICHAEL C. MOORE,Department of Chemistry and Biochemistry, Oberlin College, Oberlin, OH 44074, USA
TONY MASIELLO, Environmental and Molecular Sciences Laboratory, Pacific Northwet National Laboratory, P. O. Box 999, Mail Stop k8-88, Richland, WA 99352

2. The “cis” Effect
The cis,cis isomer has the lowest energy of the three isomers.
Calculated by ACM-DFT Method.
N. C. Craig, et al., J. Phys. Chem A, 1999, 103,

3. cis,cis-1,4-difluorobutadiene

5. Overall Structure of One C-type Band

6. Detail of Assignment in R Branch

7. Overall Structure of One C-type Band

8. Detail of Assignment in P Branch

9. Center of C-Type Band

10. Overall Structure of Second C-type Band

11. Detail of Assignment in R Branch

12. Loomis-Wood Display of Overlapping PPK Series
PP13 brown; PP14 green; PP15 red; PP16 blue; PP17 black;
PP18 yellow; PP19 magenta

13. Rotational Constants

14. Conclusions
Rotational analysis of nonpolar ccDFBD depends on high-resolution ( cm-1) infrared spectroscopy.
Rotational structure in 2 C-type bands has been analyzed.
Hot bands from the torsional mode at 78 cm-1 cause very congested spectra.
GS and US rotational constants are reported for 11(au) at 763 cm-1 and 12(au) at 327 cm-1.
First step toward an equilibrium structure for ccDFBD.

15. Support Oberlin College Dreyfus Foundation.
Pacific Northwest National Laboratory Operated by Battelle as a DOE Contractor.
Oberlin College