Polarization and Strong Infra-Red Activity in Compressed Solid Hydrogen

Abstract

Under a pressure of ~150 GPa solid molecular hydrogen undergoes a phase transition accompanied by a dramatic rise in infra-red absorption in the vibron frequency range. We use the Berry's phase approach to calculate the electric polarization in several candidate structures finding large, anisotropic dynamic charges and strongly IR-active vibron modes. The polarization is shown to be greatly affected by the overlap between the molecules in the crystal, so that the commonly used Clausius-Mossotti description in terms of polarizable, non-overlapping molecular charge densities is inadequate already at low pressures and even more so for the compressed solid.

To appear in Phys. Rev. Lett

References in corpus (1)

• Metric tensor as the dynamical variable for variable cell-shape molecular dynamics

Cited by in corpus (4)

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• Dipole-quadrupole interactions and the nature of phase III of compressed hydrogen
• Wannier-function description of the electronic polarization and infrared absorption of high-pressure hydrogen
• Ab initio Hartree-Fock Born effective charges of LiH, LiF, LiCl, NaF, and NaCl