Multivariate homogeneous rational functions, analogous to Pade approximants, are proposed for the modeling of mixture properties. They are defined as the ratio of two homogeneous Scheffe K polynomials. This choice offers a flexible functional form, attractive symmetries, parameter parsimony, and consistent expressions for multicomponent mixtures. The proposed rational functions satisfactorily correlate the nonlinear behavior of diverse multicomponent physical property data. They also extend the application of classic binary activity coefficient models such Porter, Margules, Scatchard, etc., to multicomponent mixtures.