TY - JOUR

T1 - A crossover from metal to plasma in dense fluid hydrogen

AU - Sumi, Tomonari

AU - Sekino, Hideo

N1 - Funding Information:
This work was partly supported by Grant-in-Aid for Science Research from the Ministry of Education, Culture, Sports, Science and Technology (No. 17300094) and CREST-JST.

PY - 2006

Y1 - 2006

N2 - Thermodynamic properties in dense fluid hydrogen are studied by using a density-functional theory for electron-proton binary mixtures that is called quantal hypernetted-chain (QHNC) integral equation. A nonlocal approximation for the exchange-correlation potential in a finite-temperature Kohn-Sham equation is presented. Results obtained from the QHNC with the nonlocal approximation are compared with those obtained from the QHNC with a local density approximation. Temperature variation of thermodynamic quantities between 104 and 106 K are investigated along an isochor specified by a dimensionless density parameter of rs =0.5. These quantities obtained from the QHNCs show that a crossover from metal to plasma occurs around a temperature of T=1.78× 105 K. Electrical resistivity Re of the dense fluid hydrogen evaluated from a Ziman formula [The Properties of Liquid Metals, edited by S. Takenohi (Wiley, New York, 1973)] extended to finite temperature is about 0.7 μ cm at T= 104 K. The dense fluid hydrogen at the temperature can be considered as a metallic fluid, because the value is smaller than typical values of Re in alkali metals at room temperature. The Re slightly increases with the temperature increase, and the temperature valuation of Re is monotonic. We clearly show that the contribution from the electronic excited states plays an important role for the sharp crossover from the metal to the plasma, and that the crossover is interpreted as a crossover from degenerate electron gas to nondegenerate electron gas.

AB - Thermodynamic properties in dense fluid hydrogen are studied by using a density-functional theory for electron-proton binary mixtures that is called quantal hypernetted-chain (QHNC) integral equation. A nonlocal approximation for the exchange-correlation potential in a finite-temperature Kohn-Sham equation is presented. Results obtained from the QHNC with the nonlocal approximation are compared with those obtained from the QHNC with a local density approximation. Temperature variation of thermodynamic quantities between 104 and 106 K are investigated along an isochor specified by a dimensionless density parameter of rs =0.5. These quantities obtained from the QHNCs show that a crossover from metal to plasma occurs around a temperature of T=1.78× 105 K. Electrical resistivity Re of the dense fluid hydrogen evaluated from a Ziman formula [The Properties of Liquid Metals, edited by S. Takenohi (Wiley, New York, 1973)] extended to finite temperature is about 0.7 μ cm at T= 104 K. The dense fluid hydrogen at the temperature can be considered as a metallic fluid, because the value is smaller than typical values of Re in alkali metals at room temperature. The Re slightly increases with the temperature increase, and the temperature valuation of Re is monotonic. We clearly show that the contribution from the electronic excited states plays an important role for the sharp crossover from the metal to the plasma, and that the crossover is interpreted as a crossover from degenerate electron gas to nondegenerate electron gas.

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U2 - 10.1063/1.2390704

DO - 10.1063/1.2390704

M3 - Article

AN - SCOPUS:33845329552

VL - 125

JO - Journal of Chemical Physics

JF - Journal of Chemical Physics

SN - 0021-9606

IS - 19

M1 - 194526

ER -