15min:

J. XIN, Department of Physics and Engineering Technologies, Bloomsburg University, Bloomsburg, PA 17815; H. FAN, I. IONESCU, C. ANNESLEY AND S. A. REID, Department of Chemistry, Marquette University, Milwaukee, WI 53233.

To investigate the ¹⁹F and ¹H nuclear hyperfine structure and Zeeman effect in the simplest singlet carbene, HCF, we recorded polarization quantum beat spectra (QBS) of ^rR₀(J) lines of the pure bending transitions 2₀ⁿ and combination bands 1₀¹2₀ⁿ and 2₀ⁿ3₀¹ in the HCF A¹A''-X¹A' system. The spectra were measured under jet-cooled conditions using a pulsed discharge source, both at zero-field and under application of a weak magnetic field (< 30 G). Analysis yielded the nuclear spin-rotation constants (C_aa) and weak field Lande g_aa factors. Consistent with theoretical expectations, the majority of vibrational levels exhibit a linear correlation of C_aa and g_aa, from which the a hyperfine constants were estimated. The derived values are consistent with expectations based on the known hyperfine constants of related molecules.