Universal free energy correction for the two-dimensional one-component   plasma
  The universal finite-size correction to the free energy of a two-dimensional Coulomb system is checked in the special case of a one-component plasma on a sphere. The correction is related to the known second moment of the short-range part of the direct correlation function for a planar system. 
Bernard Jancovici and Emmanuel Trizac (Physique Theorique, Orsay)