Electronic energy gap of molecular hydrogen from electrical conductivity measurements at high shock pressures

Abstract

Electrical conductivities were measured for liquid ${\mathrm{D}}_2$ and ${\mathrm{H}}_2$ shock compressed to pressures of 10–20 GPa (100–200 kbar), molar volumes near 8 ${\mathrm{cm}}^3$/mol, and calculated temperatures of 2900–4600 K. The semiconducting energy gap derived from the conductivities is 12 eV in good agreement with recent quasiparticle calculations and with oscillator frequencies measured in diamond-anvil cells.