The temperature dependences of the 35 C1 NQR frequency (v), spin-lattice relaxation time (T^), and spin-spin relaxation time (T 2) have been studied in 2,4,6-trinitrochlorobenzene (picryl chloride) from 77 K up to the melting point (354 K). The 7\ (T) curve exhibits a pronounced composite mimimum near 300 K which gives evidence for the reorientations of the two ort ho-N0 2 groups around their two-fold symmetry axes with the activation energies of 27.4 kJ mol 1 and 31.2 kJ mol 1 . These values can be related to the ortho-N0 2 groups having the twist angles of 33° and 81°, respectively (the crystal structure of picryl chloride is known). The T 2 (T) dependence exhibits interesting features, too: a deep minimum about 140 K and a new rapid decrease above 270 K.