NMR characterization of partially deuterated γ-glycine

Mobility in γ-glycine can be measured by proton relaxation or line-shape analysis of wide-line 2H spectra of deuterium-substituted γ-glycine. The temperature dependence of the wide-line 2H spectra indicates an activation energy of 33±2 kJ/mol, in agreement with the activation energy extracted from proton spin–lattice relaxation times. The proton spin–lattice relaxation time of the protons in partially deuterated γ-glycine is 78 s, much longer than the 4-s T1 of the undeuterated material. The comparison demonstrates how effectively the amine protons act as a relaxation sink.