Specific-heat disparity and multiphase thermal mass density oscillation.^[79] (a) Intersection points define the quasisolid phase (QS) whose boundaries close to temperatures for homogeneous ice nucleation (T_N) and melting (T_m). Molecular undercoordination disperses the QS boundary outwardly by H–O contraction and O:H elongation through Einstein’s relation. (b) Segmental specific-heat ratio defines the thermal slope of density over all phases for water ice and the critical temperatures vary with volume size at the nanometer scale (T ≥ 273 K bulk water; T ≤ 273 K 1.4 nm sized droplet).^[21]