Spin-lattice relaxation times T-1 and T-1d as well as NMR second moment were employed to study molecular dynamics of pyridoxine (vitamin 136) in the temperature range 10-350 K. The T-1 minimum observed at low temperatures at 200 MHz is attributed to a motion of methyl group. The motion is interpreted in terms of Haupt's theory, which takes into account the tunneling assisted relaxation. At low temperatures, where T-1 is temperature independent, occupation of the ground state only is assumed. A motion of proton of the hydroxyl groups or CH2OH groups probably provides additional mechanism of relaxation, in the high-temperature region.
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