Volume effects on the nuclear quadrupole resonance transition frequency

A suitable modification of a general thermodynamic procedure to correct experimental data, usually gathered at constant (room) pressure, to that which would be obtained had the volume been kept constant, the normal condition under which the theory is worked out. This allows therefore meaningful comparison of data with theory. This modification is applied to the pressure derivative at constant temperature of the Nuclear Quadrupole Resonance transition frequency as a function of the temperature. It is shown in p-dichlorobenzene and in p-chlorophenol that, by using very reasonable values for the various parameters appearing in the procedure, excellent agreement is found between theory and experimental data.