15min:

KEI-ICHI NAMIKI, J. SCOTT ROBINSON AND TIMOTHY C. STEIMLE, Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287.

The Stark effect on the ^qR₂₂(0,0.5) (= 17682.9251 cm^-1) and ^qP₁₁(0,1.5) (= 17682.1966 cm^-1) branch features of the (0,0)B²A₁-X²A₁ band system of calcium methoxide, CaOCH₃, was measured and analyzed to give the permanent electronic dipole moments, µ, of 1.58(8)D and 1.21(5)D for the X²A₁ and B²A₁ states, respectively. The dipole moments are compared with other monovalent calcium compounds and those predicted from a simple electrostatic model. Pure rotational transitions in the X²A₁ state were recorded using the pump/probe microwave-optical double resonance technique. The proton magnetic hyperfine splitting pattern confirms that the symmetry of the ground electronic state is C_3v. The determined small negative value for the Fermi contact parameter (a_F= -0.419 MHz) is interpreted in terms of spin polarization effects. The determined spin-rotational parameter ((\epsilon_bb+\epsilon_cc)/2 = 12.45 MHz ) is compared to that of other monovalent calcium compounds and interpreted in terms of the proposed state distribution.