The rotational spectrum and complete heavy atom structure of the chiral molecule verbenone

As the first step of a two-part chiral tagging experiment, the spectrum and subsequent isotopologue analysis on the heavy atoms of (1S)-(-)-Verbenone is presented. The spectrum has been recorded up to 69 GHz on three spectrometers, one CP-FTMW spectrometer from the University of Virginia functional from 2 to 8 GHz, a CP-FTMW spectrometer operational in the 6–18 GHz range located at the Missouri University of Science and Technology, and a Stark-modulated spectrometer operational from 48 to 72 GHz. 1250 transitions have been assigned to the parent and isotopologues for the predominantly b-type spectrum. Rotational constants and quartic centrifugal distortion constants have been determined for the parent species while for the 11 isotopologues only rotational constants have been determined. A Kraitchman analysis has been performed and the resulting coordinates are reported. The experimental heavy-atom structure has been compared to previously studied bicyclic terpenes and the computational structure and is found to be in excellent agreement with both, showing reliability of the theoretical approaches needed for the future chiral tagging work.