Electronic structure, thermodynamic properties and metallic behaviours of hydrogen

Abstract

One-dimensional metallic hydrogen chain composed of 50 hydrogen atoms in eight different lengths are theoretically investigated in different aspects and some properties are generalised to three cubic systems. Also, electrochemical and thermodynamic properties including density, pressure, specific volume, atomic packing factor and Gibbs free energies of their redox reactions are calculated and compared with experimental results, if any. It was found that chains with length close to 45 Å (corresponding to interatomic distance of ∼1 Å) and less are metallic, with regard to Wigner-Huntington transition pressure. Finally, density of states of the one-dimensional systems were calculated to get insight into their metallic behaviour. Highlights Density and pressure of metallic hydrogens are estimated in different states. One-dimensional metallic hydrogen chains are theoretically evaluated. Calculated properties are generalised to three cubic systems and close results to experimental reports were found.