Thermodynamic Properties of Gaseous Plasmas in the Limit of Extremely Low Temperature

Limiting structure of thermodynamic functions of gaseous plasmas is under consideration in the limit of zero temperature and density. Remarkable tendency, which was claimed previously (Iosilevskiy and Gryaznov, 1985) is carried to extreme. Both equations of state, thermal and caloric ones obtain in this limit identical stepped structure ("ionization stairs") for plasma of any single element when this limit (T -> 0, n -> 0) is carried out at fixed value of chemical potential for electrons (or atoms). The same stepped structure is valid for plasma of mixtures or compounds. This structure appears within a fixed (negative) range of chemical potential of electrons bounded below by value of major ionization potential of element and above by the value depending on sublimation energy of substance. Binding energies of all possible bound complexes (atomic, molecular, ionic and clusters) in its ground state are the only quantities that manifest itself in meaningful details of this limiting picture as location and value of every step. The sublimation energy this collection ("intrinsic energy scale"). All thermodynamic differential parameters (heat capacity, compressibility, etc.) obtain their remarkable betta-like structures in the zero-temperature limit ("thermodynamic spectrum"). All "lines" of these "spectrum" are centralized just at the elements of the intrinsic energy scale. The limiting EOS stepped structure of gaseous zero-Kelvin isotherm is generic prototype of well-known "shell oscillations" in EOS of gaseous plasmas at low, but finite temperature. This limiting form of plasma thermodynamics could be used as a natural basis for rigorous deduction of quasi-chemical approach ("chemical picture") in frames of temperature (not density!) asymptotic expansion around this reference system.Comment: 5 pages, 6 figures, Int. Conference "Physics of Non-Ideal Plasma" (PNP-13), Chernogolovka, Russia, September 200

Plasma polarization in high gravity astrophysical objects

Macroscopic plasma polarization, which is created by gravitation and other mass-acting (inertial) forces in massive astrophysical objects is under discussion. Non-ideality effect due to strong Coulomb interaction of charged particles is introduced into consideration as a new source of such polarization. Simplified situation of totally equilibrium isothermal star without relativistic effects and influence of magnetic field is considered. The study is based on variational approach combined with "local density approximation". It leads to two local forms of thermodynamic equilibrium conditions: constancy for generalized (electro)chemical potentials and/or conditions of equilibrium for the forces acting on each charged specie. New "non-ideality potential" and "non-ideality force" appear naturally in this consideration. Hypothetical sequences of gravitational, inertial and non-ideality polarization on thermo- and hydrodynamics of massive astrophysical objects are under discussion.Comment: 6 pages, no figures, 35 refs, Int. Conference "Physics of Non-Ideal Plasmas" (PNP-13), Chernogolovka, September 2009, Russi

How Multivalency controls Ionic Criticality

To understand how multivalency influences the reduced critical temperatures, Tce (z), and densities, roce (z), of z : 1 ionic fluids, we study equisized hard-sphere models with z = 1-3. Following Debye, Hueckel and Bjerrum, association into ion clusters is treated with, also, ionic solvation and excluded volume. In good accord with simulations but contradicting integral-equation and field theories, Tce falls when z increases while roce rises steeply: that 80-90% of the ions are bound in clusters near T_c serves to explain these trends. For z \neq 1 interphase Galvani potentials arise and are evaluated.Comment: 4 pages, 4 figure

Aging and ultra-slow equilibration in concentrated colloidal hard spheres

We study the dynamic behaviour of concentrated colloidal hard spheres using Time Resolved Correlation, a light scattering technique that can detect the slow evolution of the dynamics in out-of-equilibrium systems. Surprisingly, equilibrium is reached a very long time after sample initialization, the non-stationary regime lasting up to three orders of magnitude more than the relaxation time of the system. Before reaching equilibrium, the system displays unusual aging behaviour. The intermediate scattering function decays faster than exponentially and its relaxation time evolves non-monotonically with sample age.Comment: Submitted to the proceedings of the 6th EPS Liquid Matter Conference, Utrecht 2-6 July 200