Ideal gas behavior of a strongly-coupled complex (dusty) plasma
  In a laboratory, a two-dimensional complex (dusty) plasma consists of a low-density ionized gas containing a confined suspension of Yukawa-coupled plastic microspheres. For an initial crystal-like form, we report ideal gas behavior in this strongly-coupled system during shock-wave experiments. This evidence supports the use of the ideal gas law as the equation of state for soft crystals such as those formed by dusty plasmas. 
Neil P. Oxtoby, Elias J. Griffith, C\'eline Durniak, Jason F. Ralph,   Dmitry Samsonov
physics.plasm-ph physics.flu-dyn