The structural, electronic, and dynamical properties of molecular hydrogen under pressure are investigated by first-principles calculations. A detailed study of the $Cmca$ phase, believed to be the stable phase at very high pressure, reveals the mechanisms of metallization and their impacts on the electronic and dynamical properties which are at the basis of the predicted onset of high-temperature superconductivity in molecular ${\text{H}}_2$. Pressure is shown to greatly affect the electronic and dynamical properties of this system acting on different and connected aspects, namely, Fermi surfaces, phonon softenings, charge transfer, all of them concurring as propitious features to the onset of high-temperature superconductivity.

• Received 7 January 2010

DOI:https://doi.org/10.1103/PhysRevB.81.134505