The ionization of carbon at 10-100 times the diamond density and in the 10 K temperature range
arXiv:2105.05707 · doi:10.1103/PhysRevE.104.015201
Abstract
The behaviour of partially ionized hot compressed matter is critical to the study of planetary interiors as well as for nuclear fusion studies. A recent quantum study of carbon in the 10-70 Gbar range and at a temperature of 100 eV used -atom density functional theory (DFT) with -64 and molecular dynamics (MD). This involves band-structure type electronic calculations and averaging over many MD generated ion configurations. The calculated average number of free electrons per ion, viz., , was systematically higher than from a standard average atom (AA) quantum calculation. To clarify this offset, we examine (a) the effect of the self-interaction (SI) error in such estimates (b) the possibility of carbon being a granular plasma containing Coulomb crystals. The possibility of `magic-number' bound states is considered. The electrical conductivity, pressure, and the compressibility of the carbon system are examined. The very low conductivity and the high results of DFT-MD point to the existence of carbon in a complex non-uniform low-conducting dispersed phase, possibly containing magic-number Coulomb crystals. The NPA estimate of , conductivity, compressibility, and pressure reported here pertain to the {\it uniform liquid}.
9 pages, four figures
References in corpus (5)
- Classical and quantum Coulomb crystals
- Carbon ionization at Gbar pressures: an ab initio perspective on astrophysical high-density plasmas
- Isochoric, isobaric and ultrafast conductivities of aluminum, lithium and carbon in the warm dense matter (WDM) regime
- Efficacy of the Radial Pair Potential Approximation for Molecular Dynamics Simulations of Dense Plasmas
- Simple pair-potentials and pseudo-potentials for warm-dense matter and general applications