INTERPRETATION OF H-1-NMR RESULTS OF HD IMPURITIES IN SOLID H-2 .2. ANISOTROPIC RESONANCE FREQUENCY-SHIFTS

The anisotropic resonance frequency shift delta-v = v(HD) - v(ortho-H-2 singles) of the H-1 resonance spectrum observed in low ortho-concentration (X less-than-or-equal-to 0.01) solid H-2 single crystal samples is examined. The observed sign and magnitude of the resonance frequency shift as well as its anisotropy are explained by the spin-rotation interaction and the second order effects of the intra-molecular dipole-dipole interaction of ortho-H-2 singles. The calculations, without adjustable parameters, are in reasonable agreement with the experiments. This conclusion is at variance with the suggestion by Delrieu and Sullivan.