Deuterium and Nitrogen-14 Nuclear Quadrupole Double Resonance Studies of Hydrogen Bonding

208 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1986.The rearrangement in charge that accompanies formation of N-H...O and N-H...N hydrogen bonds in the solid state was investigated via deuterium and nitrogen-14 nuclear quadrupole resonance (nqr) spectroscopy. The experimental techniques of double resonance with level crossing and double resonance with continuous coupling were employed to detect quadrupolar transitions.('2)H nqr spectra are reported for an extensive collection of N-H...O and N-H...N hydrogen bonds exhibiting a range of proton donor and acceptor characteristics and hydrogen bond geometries. In addition, both ('2)H and ('14)N nqr data are reported for a series of hydrogen bonded complexes formed between cytosine and derivatives of amino acids.Empirical correlations between ('2)H quadrupole coupling constants and N...O and N...N distances are presented which show that the electric field gradient at a hydrogen bonded deuteron is sensitive to variations in formal charge and bonding configuration at the proton donor as well as to hydrogen bond geometry. The ('14)N nqr results are interpreted in terms of electronic charge shifts that occur at a nitrogen site as a function of N-H...O hydrogen bond strength.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD