Knowledge Bank

Radiofrequency electric resonance spectra of $SO2$ molecular beams have been observed for a number of rotational levels of the (000), (100), (010), (001), (200), (110), (020) and (001) vibrational states. Heated supersonic nozzle beams of $SO2$ in argon were found to give enhanced signal-to-noise ratios. Stark effect measurements for the vibrational ground state give $\mu 000=1.63305(4)D$ and polarizability anisotropies of $\alpha aa-\alpha bb=1.62(40)A3$ and $\alpha aa-\alpha cc=0.1(7)A3$. The dipole moment date for excited vibrational states can be expressed as $\mu =1.62673+0.00017(v1+1/2)-0.00684(v2+1/2)+0.01943(v3+1/2)-0.00002(v1+1/2)2+0.00002(v1+1/2)(v2+1/2)-0.00003(v2+1/2)2-0.00012(v2+1/2)(v3+1/2)$. By combining the Stark effect data with infrared intensity measurements, the electric dipole moment function for $SO2$ through second derivative terms has been determined.