Metal-nonmetal transition in dense hydrogen plasma

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:212785

Reinholz, H; Redmer, R; Nagel, S ^[1]

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1. Universitaet Rostock (Germany)

A quantum statistical approach to the equation of state and the transport properties of partially ionized hydrogen plasma is utilized to determine the region of thermodynamic instability and the location of the metal-nonmetal transition. The elementary electrons e and protons p as well as two-particle states are treated correctly within a physical picture. The influence of higher clusters such as dimers H{sub 2} and molecular ions H{sub 2}{sup +}, however, is studied within the chemical picture. For this, the two-particle partition function is calculated by means of an improved Beth-Uhlenbeck formula. Nonideality corrections due to the interaction between the various species are considered in the respective laws of mass action. A thermodynamic instability is found for the strongly coupled plasma domain. The critical point at T{sub c} = 16.5 x 10{sup 3} K, {wp}{sub c} = 0.42 g/cm{sup 3}, and p{sub c} = 57 GPa coincides with earlier results for this hypothetical plasma phase transition. Near the instability region, all species have strongly varying concentrations which indicates the significant influence of nonideality corrections on the thermodynamic functions. The transport properties are studied from the weakly coupled, nondegenerate region up to strongly coupled, degenerate domain. Such a universal approach which includes the Spitzer as well as the Ziman theory as limiting cases can be formulated within linear response theory. Again, two-particle correlations have been accounted for by the correct quantum cross sections for electron scattering at ions and free electrons. Electron scattering at neutral atoms was considered on T matrix level with respect to an effective optical potential. Strong ion-ion correlations are of special importance at high densities. The respective ion-ion structure factor was determined numerically within the HNC scheme, taking into account local-field corrections to the screening function of the effective ion-ion interaction potential.

• OSTI ID: 212785
• Report Number(s): CONF-950749--
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
66 PHYSICS
ELECTRIC CONDUCTIVITY
EQUATIONS OF STATE
HYDROGEN
ION-ION COLLISIONS
PARTITION FUNCTIONS
PHASE TRANSFORMATIONS
PLASMA
THERMODYNAMIC PROPERTIES