%0 Journal Article %T Millimeter-Wave Rotational Spectrum, Barrier to Internal Rotation, and DFT Calculation of o-Tolunitrile %A A. I. Jaman %A P. Hemant Kumar %A P. R. Bangal %J Journal of Atomic, Molecular, and Optical Physics %D 2011 %I Hindawi Publishing Corporation %R 10.1155/2011/480396 %X The millimeter-wave rotational spectra of o-tolunitrile (C6H4CH3CN) have been investigated in the ground torsional state in the frequency range 50.0–75.0 GHz. Many high-J rotational lines with large A-E splitting due to internal rotation of the methyl top have been assigned. A least squares analysis of the A-E splitting of 92 transitions resulted in the determination of accurate values of internal rotation parameters. The observed parameters were compared with the previously reported experimental values and DFT calculation results. %U http://www.hindawi.com/journals/jamop/2011/480396/