  We use the density functional method to examine the properties of the
nonuniform (two-phase) fluid of two-level atoms, a part of which is excited.
Basing on the analysis of the equation of state of a gas of two-level atoms, a
part of which is excited, we suggest a simple density functional of the grand
thermodynamical potential. We use the proposed density functional of the grand
thermodynamical potential to calculate the nucleation barrier for
vapor-to-liquid phase transition in the presence of excited atoms.
