On the Nature of the “Bleaching out” Process of the ³⁵Cl NQR Signals in 1,2,3-Trichlorobenzene

The combination of X-ray diffraction and nuclear quadrupole resonance studies of crystals

“…Using crystals of 1,2,3-trichlorobenzene-d3, the 2H NMR spectra were studied at 193 and 295 K. Within 0.5 °, @= is parallel to the bond direction C--CI for the six inequivalent CI atoms, r/(35C1) is between 0.06 and 0.07, 176 < eQ@zz h-I < 178 MHz. That the 2H NMR fades out as the 35C1 NQR does, a model of orderdisorder in 1,2,3-C13C6H 3 was developed (Wigand, Weiden & Weiss, 1990). Refinement of the crystal structure by neutron diffraction on 1,2,3-C13C6D3 at two temperatures gives, however, no indication for orderdisorder.…”