Missing short-range interactions in the hydrogen bond of compressed ice

TL;DR

This paper investigates the often-overlooked short-range interactions in the hydrogen bonds of compressed ice, revealing their critical role in ice's anomalous properties through a novel mechanical approach.

Contribution

It introduces a combined Lagrangian-Laplace mechanics method to quantify short-range interactions and their pressure dependence in hydrogen bonds of ice, highlighting their importance.

Findings

Compression shortens and stiffens the OH bond.

Compression lengthens and softens the covalent bond.

Inter-electron-pair Coulomb repulsion is essential in bond dynamics.

Abstract

Combining the Lagrangian-Laplace mechanics and the known pressure dependence of the length-stiffness relaxation dynamics, we have determined the critical, yet often-overlooked, short-range interactions in the hydrogen bond of compressed ice. This approach has enabled determination of the force constant, cohesive energy, potential energy of the vdW and the covalent segment at each quasi-equilibrium state as well as their pressure dependence. Evidencing the essentiality of the inter-electron-pair Coulomb repulsion and the segmental strength disparity in determining the asymmetric H-bond relaxation dynamics and the anomalous properties of ice, results confirmed that compression shortens and stiffens the OH bond and meanwhile lengthens and softens the covalent bond.