Structural organizations in supercooled liquid 2-biphenylmethanol

IR spectroscopy and differential scanning calorimetry measurements have been undertaken to obtain new information about structural organizations in supercooled liquid hydrogen-bonded 2-biphenylmethanol and to estimate the change of the hydrogen bond energy during the vitrification process. It has been found that the energy of the hydrogen bond increases from 3.8 kcal/mol in the liquid state to 4.9 kcal/mol at the glass transition temperature (Tg) and continues to increase below Tg reaching the value of about 5.4 kcal/mol at 12 K. Upon heating of the glassy state through the glass transition region and above, the structural organizations expand into metastable phase with local structure differing from that in the stable phase.