ELECTRONIC-ENERGY GAP OF MOLECULAR-HYDROGEN FROM ELECTRICAL-CONDUCTIVITY MEASUREMENTS AT HIGH SHOCK PRESSURES

Electrical conductivities were measured for liquid D2 and H-2 shock compressed to pressures of 10-20 GPa (100-200 kbar), molar volumes near 8 cm3/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.