The temperature dependence of 14N pure quadrupole resonance in 4- and 3-cyanopyridines

In this paper it is shown that the temperature dependence of the ¹⁴N pure quadrupole resonance for both cyanide and pyridine nitrogen atoms in cyanopryidines may be used to relate the orientation of the electric field gradient tensor at the cyanide site to that at the pyridine. This provides a means to discuss the population of the two π orbitals on the cyanide nitrogen atom.