Motion of each ring in the p-terphenyl moiety of the mesogenic unit in polyester-di-Me siloxanes began at 5-10 Deg below the transition temp. into the liq-cryst. state as detd. from 13C magic-angle-spinning NMR spectra. The sudden onset of motion suggested a jump of the arom. rings over a 45-50 Deg rotational angle. Comparison of NMR data with theor. data indicated that intermol. forces detd. the obsd. motion.