15min:

BEAU J. BARKER, IVAN O. ANTONOV AND MICHAEL C. HEAVEN, Department of Chemistry, Emory University, Atlanta, GA 30322.

Theoretical calculations predict that internal electric fields as high as 90 GV/cm can be attained by polarizing the ³ ₁ state of ThF⁺ Consequently, this ion is of interest for investigation of the dipole moment of the electron. However, spectroscopic data have not been reported previously for ThF or ThF⁺. We have used laser induced fluorescence and resonantly enhanced two-photon ionization to examine ThF. Multiple electronic transitions were observed in the 19530-21300 cm^-1 range. Rotationally resolved data have been obtained, and the ground state is shown to be X² _3/2. Pulsed field ionization - zero electron kinetic energy spectra have been recorded for the ThF+ cation. Vibronic progressions of the X^{1 +} and excited ³ states have been identified. The term energy for the ³ ₁ state was found to be T₀=330 cm^-1. Details of the experiments and spectroscopic constants for ThF and ThF⁺ will be reported.