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Using orbital-free molecular dynamics simulations we study the structure and dynamics of increasingly asymmetric mixtures such as hydrogen-carbon, hydrogen-aluminium, hydrogen-copper, and hydrogen-silver. We show that, whereas the heavy component structure is close to an effective one-component plasma ( OCP), the light component appears more structured than the corresponding OCP. This effect is related to the crossover towards a Lorentz-type diffusion triggered by strongly coupled, highly charged heavy ions, and witnessed by the change of temperature scaling laws of diffusion. This over-correlation translates into an enhancement of nuclear reaction rates much higher than its classical OCP counterpart. [ABSTRACT FROM AUTHOR]

When heated at constant volume (isochoric heating) a hot and dense plasma (10-5000 eV, 1-50 g/cm3) exhibits the same persistent microscopic structure over a wide range of temperatures as intuited long time ago by Laughlin [1]. In this steady-state regime, which depends on the chosen density and on the atomic number, the static structure is essentially independent of the temperature and results in the subtle balance between ionization and temperature leading to a constant coupling between ions. This behavior, suggested by simulations, is confirmed by an analysis in the framework of the Thomas-Fermi scaling laws and is driven by the ionization dynamics which regulates the coupling between ions and electrons. A simple fit is derived allowing for predicting the occurrence of this self-organized regime: the Γ-plateau. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]