MOLECULAR MOBILITY OF SUCROSE IN AQUEOUS-SOLUTION STUDIED BY C-13 NMRRELAXATION

From the temperature and concentration dependence of the C-13 spin lat tice relaxation times of the 12 carbon atoms of the sucrose molecule t he rotational dynamics of the sugar molecules are determined. No indic ation for conformational mobility of the rings is found. The exocyclic hydroxymethyl groups possess extra mobility. The models used for the description are critically discussed. The temperature dependence of th e rotational mobility is described by a VTF equation. The concentratio n dependence of the ideal glass transition temperature T(o) for this m obility is derived.