title: p-Chlorobenzotrichloride revisited: novel analytical treatments of 2D exchange NQR in molecular crystals.
abstract: A theoretical treatment of the two-dimensional exchange nuclear quadrupole resonance pulse sequence is presented and applied to the quantitative study of exchange processes in molecular crystals. The theory is successfully tested for the exchange spectra of hindered trichloromethyl groups of p-chlorobenzotrichloride, where the conventional approach without taking into account the off-resonance phenomena has failed. The mixing dynamics by exchange and the expected diagonal- and cross-peak intensities as a function of the mixing time have been derived. It is shown that the off-resonance effects are of crucial importance for the quantitative description of the exchange spectra.
authors.forename: Mariusz
authors.initials: M
authors.lastname: Mackowiak
mesh_terms: D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D015394:Molecular Structure
chemical_list: D006843:Hydrocarbons, Chlorinated; C559580:p-chlorobenzotrichloride