Nuclear quadrupole and magnetic resonance studies of structure and the molecular motion in SYMC6Cl3F3

35Cl and 19F relaxation time measurements were carried out on symC6Cl3F3. The analyses of the 19F high-resolution NMR spectra and the 35Cl spin-lattice relaxation time showed that the crystal belongs to a trigonal or a hexagonal crystal system in which the molecules undergo three-fold reorientation about the molecular figure axis with the correlation time τc/s=3.42·10−7 exp(18.2 kJ mol−1/RT). Temperature dependences of the 35Cl NQR frequency and 19F spin-lattice relaxation times are such that only a minor structural change is associated with the phase transition at 296 K.