35Cl NQR study of CCl3 reorientations in the carbonyl-containing derivatives of 3,3,3-trichloropropene

Temperature dependences of35Cl NQR frequencies and spin-lattice relaxation times were measured for the CCl3 groups of compounds CCl3CH=CHR and CCl3CH=CR2 with R=COCH3 and COOCH3. The activation energies of CCl3 reorientations reflect the significant contribution of intermolecular steric interactions to the value of the potential barrier hindering these reorientations. In the CCl3CH=CHCOCH3 crystal, the reorientations of the CCl3 group are hindered more than those of the molecule as a whole.