Liquid water stability as network resilience
Liquid water is unusually stable, remaining liquid across a wide range of temperatures and even when confined to spaces only a few molecules wide. Yet it eventually fails in both settings: boiling at the critical temperature or drying in narrow pores, phenomena normally studied separately. Water's hydrogen-bond network is thought to underlie this stability, but tracking bond survival has not resolved the puzzle. Extending a concept we recently introduced for wetting (J. Am. Chem. Soc. 148, 21572 (2026)), we show that these stability limits can be accurately derived from a previously overlooked network property: resilience, the capacity to locally repair a broken bond. Only interactions too weak to be repaired constitute genuine defects, a far smaller population than conventional definitions suggest. While intact bonds remain abundant up to failure and conventionally broken bonds already percolate well before it, instability coincides with the percolation of these genuine defects. Comparing local interaction energies with a single intrinsic scale (identified a priori) predicts the wetting-hydrophobicity crossover, nanoconfinement cavitation, and bulk criticality. These phenomena are thus unified through a common molecular framework whose energetic scale also matches a long-unexplained spectroscopic feature of water. A single, parameter-free molecular criterion rooted in network resilience suffices.