DIPOLE MOMENTS OF THE GROUND AND EXCITED VIBRATIONAL STATES OF OH AND OD

Abstract

OH and OD radicals were formed in a supersonically expanded $discharge.^{1}$ The $J=3/2$ lambda doublet transition of OH could be observed in the ${^{2}}\pi_{3/2}$ state for $v=0, 1$ and 2, but lambda doublets in the ${^{2}}\pi_{1/2}$ state were not observed. This is consistent with the high vibrational ($\sim 3400^{\circ}K$) and low rotational ($\sim 10^{\circ}K$) temperature measured by Droege and Engelking. The OD radical appeared to be somewhat colder vibrationally since only the $v=0$ and 1 states were observed, the latter being very weak. The Stark effects of the $F=2\rightarrow 2$ transition of OH and the $F-5/2\rightarrow 5/2$ transition of OD in the $J=3/2, {^{2}}\pi_{3/2}$ state were measured using the molecular beam electric resonance technique. The following dipole moments were determined. [FIGURE] The dipole moment of the ground state of OH differs significantly from previous results. This deviation will be discussed.