Statistical field theory for a multicomponent fluid: The collective variables approach

Using the collective variables (CV) method the basic relations of statistical field theory of a multicomponent non-homogeneous fluids are reconsidered. The corresponding CV action depends on two sets of scalar fields fields ρα connected to the local density fluctuations of the αth species of particles and fields ωα conjugated to ρα. The explicit expressions for the CV field correlations and their relation to the density correlation functions are found. The perturbation theory is formulated and a mean field level (MF) of the theory is considered in detail. Pacs: 05.70.Fh, 02.70.Rr