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.