th  - 1987 - 51st ENC Conference

Wednesday - AM
Field Cycling NMR as a Tool for NQ~RSpectroscopy of Weakly
Quadrupole-Coupled Nuclei: Pyridine, Imidazole, and the
Nucleosides Adenosine, Guanosine and Inosine. J. L. Ragle,
Department of Chemistry, University of Massachusetts,
Amherst, MA 01003.
NMR experiments which cycle with B ° or Brf have been used
for over 3 decades for various purposes. In the case of
integer spin nuclei and in the weak quadrupole coupling
regime, very high resolution zero field spectra may be
obtained in either the time or frequency domain by several
of these techniques.
This talk discusses use of the simplest of these, adiabatic
field cycling between high field and zero field, to measure
NQR spectra in several sets of molecules: imidazole and
imidazolium salts, and three nucleosides. Quadrupole
coupling constants will be discussed in the light of
structures and MO calculations on these species.