Extention of Darken's Quadric Formalism to Dilute Multicomponent solutions

Darken's quadratic formalism is extended to multicomponent solutions. Equations are developed for the representation of the integral and partial excess free energies and enthalpies in dilute multicomponent solutions.Quadratic formalism applied to multicomponent solutions is thermodynmically consistent. The formalism is compared with the conventional second orderMaclaurin series or interaction parameter representaion and relations between them are derived. Advantages of the Quadratic formalism are discussed.