On H-dynamics of supercooled water confined in nanoporous silica

•The mean kinetic energy of the proton, Ke(H), in nanoconfined supercooled water between 25 K and 300 K, is calculated semi-empirically.•The results nicely agree with DINS measurements.•The calculation coincides with that of bulk ice, indicating no evidence for the occurrence of the liquid-liquid transition along this T range.•We conclude that Ke(H) in ordinary H2O phases and in water nanoconfined in porous silica is nearly constant between 5 K to 295 K and is hence poorly sensitive to phase transitions of a thermodynamic nature in these systems.