Fig. 3
From: The role of hydrogen bonds in hydrous minerals stable at lower mantle pressure conditions
Schematic illustration of proton distributions of the hydrogen bond in ice VIII/VII/X under pressure. (1) asymmetric hydrogen bond, (2) static disordering, hydrogen resides at one of double potential wells, (3) dynamical disordering with bimodal probability of proton (e.g., dynamically disordered ice VII) (4) dynamical disordering state with unimodal probability of proton at the midpoint of two oxygen atoms (dynamically disordered ice X), (5) symmetric hydrogen bond (ice X)