Electrostatic polarization or molecular undercoordination endows the supersolidity by shortening and stiffening the H–O bond and lengthening and softening the O:H nonbond, deepening the O 1s energy level, and prolonging the photoelectron and phonon lifetime. The supersolid phase is less dense, viscoelastic, mechanically and thermally more stable, which offsets boundaries of structural phases and critical temperatures for phase transition of the coordination-resolved core–shell structured ice such as the ‘no man's land’ supercooling and superheating.