Electrical conductivity of hydrogen shocked to megabar pressures

Conference · Sun Jul 10 04:00:00 EDT 1994 · AIP Conference Proceedings (American Institute of Physics); (United States)

OSTI ID:7167250

Weir, S T; Nellis, W J; Mitchell, A C ^[1]

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1. Lawrence Livermore National Laboratory, University of California, P.O. Box 808, Livermore, California 94550 (United States)

Electrical conductivity experiments on compressed hydrogen are valuable for determining the band gap of hydrogen at near-metallic densities, and for estimating the band-overlap metallization density of hydrogen. In our experiments, liquid hydrogen samples were quasi-isentropically compressed to megabar pressures by a reverberating shock wave, and the electrical conductivities were measured simultaneously. To check for consistency, experiments were performed with both H[sub 2] and D[sub 2]. Preliminary analysis shows that the measured electrical conductivities are consistent with an intrinsic semiconductor model in which conduction occurs by thermal excitation of charge carriers across the electronic band gap of molecular hydrogen. Thus, the conductivity measurements yield valuable information on the band gap of hydrogen at densities approaching the metallization density. Pressures ranged from 0.8 to 1.2 Mbars, and calculated temperatures from 2000 K to 3000 K. The calculated densities were near 0.3 moles/cc. Calculated temperatures are small compared to the band gap. Measured conductivities are in agreement with electronic band gap calculations for orientationally disordered hcp H[sub 2]; the theory for this situation predicts band gaps of 6.0 to 5.2 eV in this range. [copyright] 1994 American Institute of Physics

• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 7167250
• Report Number(s): CONF-921145--
• Conference Information: Journal Name: AIP Conference Proceedings (American Institute of Physics); (United States) Journal Volume: 309:1
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360606 -- Other Materials-- Physical Properties-- (1992-)
665430* -- Other Topics in Quantum Fluids & Solids-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
DENSITY
DEUTERIUM
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRONIC STRUCTURE
ELEMENTS
HYDROGEN
HYDROGEN ISOTOPES
IMPACT SHOCK
ISOTOPES
LIGHT NUCLEI
NONMETALS
NUCLEI
ODD-ODD NUCLEI
PHYSICAL PROPERTIES
STABLE ISOTOPES
TEMPERATURE RANGE
TEMPERATURE RANGE 1000-4000 K
VERY HIGH PRESSURE