Hydrogen bonding and coordination in normal and supercritical water from x-ray inelastic scattering

Article

关键词: PARRINELLO MOLECULAR-DYNAMICS;    1ST PRINCIPLES SIMULATIONS;    DENSITY-FUNCTIONAL THEORY;    SELF-DIFFUSION;    LIQUID WATER;    REARRANGEMENTS;    ENERGETICS;    NETWORK;    ICE;    ACCURACY;   

DOI  :  10.1103/PhysRevB.76.245413

来源: SCIE

【 摘 要 】

A direct measure of hydrogen bonding in water under conditions ranging from the normal state to the supercritical regime is derived from first-principles calculations for the Compton scattering of inelastically scattered x rays. First, we show that a measure of the number of electrons n(e) involved in hydrogen bonding at varying thermodynamic conditions can be directly obtained from Compton profile differences. Then, we use first-principles simulations to provide a connection between n(e) and the number of hydrogen bonds n(HB). Our study shows that over the broad range studied, the relationship between n(e) and n(HB) is linear, allowing for a direct measure of bonding and coordination in water by coupling simulations with experiments. In particular, the transition to supercritical state is characterized by a sharp increase in the number of water monomers but also displays a significant number of residual dimers and trimers.

【 授权许可】

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