Metallization of fluid molecular hydrogen at 140 GPa (1.4 Mbar)

Electrical resistivities were measured for liquid H{sub 2} and D{sub 2} shock compressed to pressures of 93{endash}180 GPa (0.93{endash}1.8 Mbar). Calculated densities and temperatures were in the range 0.28{endash}0.36 mol/cm{sup 3} and 2200{endash}4400 K. Resistivity decreases almost 4 orders of magnitude from 93 to 140 GPa and is essentially constant at a value typical of a liquid metal from 140 to 180 GPa. The data are interpreted in terms of a continuous transition from a semiconducting to metallic diatomic fluid at 140 GPa and 3000 K. {copyright} {ital 1996 The American Physical Society.}