Observation of equilibrium liquid-liquid transition in triphenyl phosphite

The thermal signature of an equilibrium liquid-liquid transition (LLT) in triphenyl phosphite was detected by differential scanning calorimetry measurements at a fast heating rate reaching 500 K min(-1). The estimated temperature, enthalpy, and entropy of the LLT were 241.7 K, 12.0 kJ mol(-1), and 49.5 J K-1 mol(-1), respectively. The estimated residual entropy for a glacial sample prepared at 224.7 K was 6 J K-1 mol(-1); this value is much smaller than that for the normal glassy liquid. This glacial state was found to be a highly ordered liquid compared with the normal glassy liquid in terms of entropy. (C) 2013 Elsevier B. V. All rights reserved.