Knowledge Bank

The rotational contour of the origin band of toluene has been computed within the framework of the asymmetric top with free internal rotation (1). With the basis |J, Ka, Kc, M, m $>$ and the barrier height equal to zero, the energy matrix becomes diagonal in the torsional quantum number, m, and the secular equation is then factorable into even and odd K sub-blocks. The selection rules for dipole radiation are the same as for the rigid asymmetric top with the additional constraint that $\Delta m = $O. A general program has been written so that the rotational band contour for any molecule in this class may be computed.