Wheeler, John
Physical chemistry: thermodynamics and statistical mechanics; phase transitions in molecularly complex systems

Contact Information
Professor Emeritus

Office: Urey Hall 3050M
Phone: 858-534-3287
Email: jwheeler@ucsd.edu
1967 Ph.D., Cornell University
1963 B.A., Oberlin College
Awards and Academic Honors
Guggenheim Foundation Fellow
Alfred P. Sloan Foundation Fellow
Postdoctoral position, Harvard University
NSF Postdoctoral Fellow, Harvard University
NSF Graduate Fellowship, Cornell University
Sigma Xi
Phi Beta Kappa
Research Interests
My principal area of research is the theory of phase transitions and critical phenomena in multicomponent mixtures. I use statistical mechanical models and general thermodynamic arguments to gain a better understanding of these systems. Currently I am particularly interested in mixtures in which the molecular complexity of the components leads to interesting new kinds of phase transitions and critical phenomena. Some examples on which I have active research projects are: hydrogen-bonded liquid mixtures with lower critical solution points and closed-loop coexistence curves; critical phenomena and phase transitions in polymers and polymer solutions; equilibrium polymerization as a critical and tricritical phenomenon and its consequences for the interesting phase transitions in sulfur, sulfur solutions, and living polymers; phase diagrams in micelle-forming surfactant solutions; phase equilibrium and critical points in microemulsions; and critical phenomena in chemically reactive mixtures. Although much of my work is analytical in nature, we currently have two research projects in this area that involve Monte Carlo simulations of polymers and microemulsions.

A second area of research is the analysis of spectral densities by moment methods. Many problems in chemistry and physics can be expressed in terms of densities, including the vibrational and electronic structure of solids, various models of magnetism, and the general study of time correlation functions. It is often the case that the density is unknown, but that several moments or averages over the density can be obtained. The problem then is to reconstruct the density from a limited number of moments. We have developed methods based on modified moments for analyzing densities and reconstructing the unknown density functions with great accuracy. We are currently applying these techniques to the properties of atoms at the surfaces of solids.

Primary Research Area
Physical/Analytical Chemistry
Interdisciplinary interests

Selected Publications