1. MICROWAVE SPECTRA OF DEUTERIUM ISOTOPOLOGUES OF cis-HEXATRIENE NORMAN C. CRAIG, VINCENT A. ALESSI, YIHUI CHEN, HENRIK EHRHARDT, EMERSON E. FRENCH, HANNAH A. FUSON, HENGFENG TIAN, and HERMAN VAN BESIEN, Department of Chemistry and Biochemistry, Oberlin College, Oberlin, OH 44074 ANDREW R. CONRAD and MICHAEL J. TUBERGEN, Department of Chemistry, Kent State University, Kent, OH 44242

2. Preliminaries

3. Deuterium isotopologues of cis-hexatriene (cHTE) investigated; 13 C species from previous work a cis-1-d 1 trans-1-d 1 a Suenram, R. D.; Pate, B. H.; Lesarri, A.; Neill, J. L.; Shipman, S.; Holmes, R. A.; Leyden, M. C.; Craig, N.C. J. Phys. Chem. A 2009, 113, 1864-1868.

7. MW lines for cHTE-1,1-d 2

8. Rotational constants for cHTE from MW spectroscopy

10. A selection of rotational constants for cHTE

12. Conclusions Various deuterium isotopologues of cHTE have been synthesized. Rotational constants have been obtained for these species by MW spectroscopy. Calculated 1/2alpha sums have given equilibrium rotational constants for 13 C and 2 H species. Kraitchman equations have given an r s /r e structure. The structure of cHTE shows greater effects of  - electron delocalization than does butadiene.

13. Acknowledgements Peter Groner, University of Missouri-Kansas City. Dreyfus Foundation, Senior Scientist Mentor grant. Oberlin College, Department of Chemistry and Biochemistry. Kent State University, Department of Chemistry. National Science Foundation for support of the Beowulf computer cluster at Oberlin College.