Phase behavior is strongly affected by dipolar interactions in a wide range of systems including those containing ketones, aldehydes, ethers, and esters. Multiple polar sites are present in various polar copolymers as well as in polyethers and polyesters. Although theories have been developed for nearly spherical polar molecules and for nonpolar chain molecules, accounting simultaneously for a single multipolar interaction and molecular shape has remained an unsolved problem of statistical-mechanics-based perturbation theory (Gray, C. G.; Gubbins, K. E. Theory of Molecular Fluids I; Clarendon Press: Oxford, U.K., 1984. Walsh, J. M.; Gang, J.; Donohue, M. D. Fluid Phase Equilib. 1991, 65, 209). Accurate accounting for the effect of multiple polar sites in nonspherical molecules has been well beyond expectation. In recent work, we solved part of this problem by showing how to accurately predict the properties of chainlike molecules with single or multiple dipolar sites (Jog, P. K.; Chapman, W. G. Mol. Phys...