Knowledge Bank

The laser-microwave double resonance (LMDR) spectroscopy with intense electric field was applied to the $\nu 5$ band of $CDF3$. The dipole moments and polarizability anisotropies in the ground and $\nu 5$ states were determined as follows, $Ground\nu 5\mu 1.653511(29) 1.658514(23)D\alpha -0.77(32)-0.58(48)A3$ where three times of standard deviations are in parentheses. The dipole moment in the ground state agrees with the result by molecular beam electric resonance, $1.653498(11D1$). The polarizability anisotropies agree with the sum of the electronic polarizability anisotropy obtained from Kerr effect and the contribution of the vibrational Stark effect. The (2,-1) interaction in the $\nu 5$ state was found to give remarkable perturbations to some rotational levels under the electric field. A new electric field dependent interaction of the (2,-1) type was found to give observable effects. The constants for this interaction as well as for the ordinary (2,-1) interaction were determined. The sign of the l-type doubling constant $q5$ was determined by means of double resonance experiment. Other molecular constants were also well determined by LMDR and Stark Lamb-dip spectroscopy.