AbstractUsing the chemical‐picture representation of plasmas as a mixture of various ions and free electrons, a consistent description of thermodynamics of dense multicharged‐ion plasmas is being developed that involves the effects of Coulomb non‐ideality and degeneracy of plasma electrons; contribution of the excited ion states (on the base of the superconfiguration approach) that may exist under an appropriate truncation of ion energy spectra due to plasma effects; hard‐sphere‐model representation of the finite‐volume effects of plasma ions with the model parameters (effective ion sizes) corresponding to superconfigurations yielding the greatest contribution to partition functions. We present the calculated data for average ionization, Grüneisen coefficient, and specific heat of aluminum and iron plasmas at temperatures of 0.03–3 keV and densities 10–3 – 10–5 of their normal material densities. Calculated thermodynamic functions and shock Hugoniots are compared with other theoretical and experimental data (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)