MEASUREMENTS OF HYPERFINE STRUCTURE IN $NONO_{2}$ AND $PH_{2}$D USING THE FLYGARE-BALLE PULSED BEAM SPECTROMETER

Abstract

The Fourier transform - pulsed beam microwave $spectrometer^{1, 2}$ developed by W.H. Flygare, T.J. Balle and coworkers allows high resolution measurements of rotational transitions on molecules which are difficult or impossible to measure using standard techniques. Previous measurements have been made on both $NONO_{2}$ and $PH_{2}D$, but at much lower resolution. Far $NONO_{2}$ hyperfine structure due to both nitrogen atoms was completely resolved and quadrupole coupling tensors were obtained. The values obtained differ significantly from those obtained for the free molecules NO and $NO_{2}$. Splitting of the rotational transitions in $PH_{2}D$ was observed due to the $^{31}P$ spin-rotation interaction and $^{1}H$ spin-rotation interaction. Deuterium quadrupole coupling and inversion splitting were not resolved. The upper limit on the Inversion splitting from these measurements is 20 KHz.