Dipole-quadrupole interactions and the nature of phase III of compressed hydrogen

Abstract

A new class of strongly infrared active structures is identified for phase III of compressed molecular H2 by constant-pressure ab initio molecular dynamics and density-functional perturbation calculations. These are planar quadrupolar structures obtained as a distortion of low-pressure quadrupolar phases, after they become unstable at about 150 GPa due to a zone-boundary soft phonon. The nature of the II-III transition and the origin of the IR activity are rationalized by means of simple electrostatics, as the onset of a stabilizing dipole-quadrupole interaction.

4 pages, 3 figures. To appear in Phys. Rev. Lett

References in corpus (2)

• Solid molecular hydrogen: The Broken Symmetry Phase
• Polarization and Strong Infra-Red Activity in Compressed Solid Hydrogen

Cited by in corpus (16)

• Phonons and related properties of extended systems from density-functional perturbation theory
• Spectroscopic Studies of the Vibrational and Electronic Properties of Solid Hydrogen to 285 GPa
• Quasi-molecular and atomic phases of dense solid hydrogen
• Fate of density functional theory in high-pressure solid hydrogen
• Room-Temperature Structures of Solid Hydrogen at High Pressures
• Quantum Monte Carlo Simulation of the High-Pressure Molecular-Atomic Crossover in Fluid Hydrogen
• Quantum phase diagram of high-pressure hydrogen
• Hexagonal structure of phase III of solid hydrogen
• Quantum Monte Carlo Study of High Pressure Solid Molecular Hydrogen
• The role of van der Waals and exchange interactions in high-pressure solid hydrogen
• Understanding high pressure hydrogen with a hierarchical machine-learned potential
• Absence of Metallization in Solid Molecular Hydrogen
• Wannier-function description of the electronic polarization and infrared absorption of high-pressure hydrogen
• Structural Phase Transition at High Temperatures in Solid Molecular Hydrogen and Deuterium
• High-pressure II-III phase transition in solid hydrogen: Insights from state-of-the-art ab initio calculations
• Optimal basis set for electronic structure calculations in periodic systems