We are attempting to improve the theoretical description of the complex behavior observed at or near the critical point for both pure species and for mixtures. This work entails modification of current equations of state and/or development of new equations of state, as well as the mixing rules that give the composition dependence of the parameters that appear in such equations.

We are developing a theory that will adequately describe the rate of nucleation in the formation of polymer foams. This phenomenon controls many of the physical properties of the resultant product, and a successful theory will allow better development of product formulations, rather than the trial-and-error approach that is the current norm.

In this work, we are taking advantage of advances in the capabilities of modern computers to evaluate properties of both molecules and parts of molecules. These properties can in turn be used to help determine parameters that can be used in engineering models. This work also involves improvement/redevelopment of these models to take advantage of the availability of parameters thus calculated. This work has exciting possibilities for greatly improving the accuracy and usefulness of engineering tools such as group-contribution methods for prediction of phase equilibrium properties, and many others.

Arturo, S. G. and Knox, D.E., "Application of Force Field in Gibbs Ensemble Lattice Statistics to Model Vapor/Liquid Equilibria, " Fluid Phase Equilibria, 252, 175-188 (2007).

Arturo, S. G. and Knox, D.E., "Structural and Electrostatic Properties of Atoms and Functional Groups using AIM Theory: Saturated Organics with one Electronegative Atom, " Journal of Molecular Structure:THEOCHEM 770, 31-44 (2006).

Knox, D.E., “Solubilities in Supercritical Fluids”, Pure Appl. Chem., 77 (3), 513-530 (2005).