Having previously found the structure of pyridine-CO2 in our lab, determining the
structure of pyridine-CS2 was a problem of immediate interest. CO2 and CS2 have opposite quadrupole moments, making the structures of the two complexes different. While scanning for rotation transitions using Fourier-transform microwave spectroscopy, several unassigned J 3->4 transitions were found around the 4 GHz region, which indicated a significantly different preliminary structure than the predicted linear geometry. The appearance of the spectrum suggests that the complex may have a dipole moment along the b-inertial axis.