Effect of vibrational averaging on the quadrupole coupling constant of deuterium in 4-[2H1] pyridine determined from1H–{2H} INDOR n.m.r. of a partially oriented sample

Abstract
Simultaneous measurement of proton and deuterium spectra of partially oriented 4-[2H1]pyridine by an INDOR experiment is shown to give an accurate measurement of the quadrupole coupling constant provided that vibrational averaging is used in the determination of orientation parameters. The effect of vibrational averaging on the structure of pyridine and [15N]-pyridine derived from N.M.R. data is found to be small.