  Orbital-free molecular dynamics simulations are used to benchmark two popular
models for hot dense plasmas: the one component plasma (OCP) and the Yukawa
model. A unified concept emerges where an effective OCP (eOCP) is constructed
from the short-range structure of the plasma. An unambiguous ionization and the
screening length can be defined and used for a Yukawa system, which reproduces
the long range structure with finite compressibility. Similarly, the dispersion
relation of longitudinal waves is consistent with the screened model at
vanishing wavenumber but merges with the OCP at high wavenumber. Additionally,
the eOCP reproduces the overall relaxation timescales of the correlation
functions associated with ionic motion. In the hot dense regime, this unified
concept of eOCP can be fruitfully applied to deduce properties such as the
equation of state, ionic transport coefficients, and the ion feature in x-ray
Thomson scattering experiments.
