Electrical conductivity of hydrogen shocked to megabar pressures

Conference · Sun Jul 10 00:00:00 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-; CODEN: APCPCS
• Journal Information: AIP Conference Proceedings (American Institute of Physics); (United States), Vol. 309:1; Conference: Production and neutralization of negative ions and beams, Upton, NY (United States), 9-13 Nov 1992; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

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