James Franck Institute

Faculty Research Summaries | Director's Introduction

Senior Research Associates

Jacek Dudowicz, Senior Research Associate

Theoretical statistical therm-odynamical studies of phase transitions in polymer systems are of a considerable interest in modern polymer physics. One of our projects deals with the description of equilibrium particle clustering, a ubiquitous phenomenon occuring in numerous systems ranging from various nanoparticle filled materials to proteins in living organisms. Given the importance of the equilibrium polymerization as a paradigm for molecular self-assembly processes, there is a need for systematic investigation of how general constraints imposed on the free assocation process, such as thermal activation and chemical initiation, influence essential thermodynamic properties of the associating solutions, and, particularly, the competition between the polymerization transition and phase separation. A generalization of the equilibrium polymerization theory to model thermodynamics of complex associating fluids (e.g., micelles, clay and colloidal dispersions, gels, etc.) is the next logical step in these studies. Another interest focuses on the glass transition phenomenon in polymer melts and blends. More specifically, our goal is to understand the relationship between monomer molecular (i.e., monomer size and shape) and glass formation (i.e. glass transition temperature and glass fragility) since this relationship is fundamental to numerous practical applications.

Kevin Gibson, Senior Research Associate

As a member of the Sibener group, my interests involve studying gas-surface interactions. The main tool for these studies is an ultra-high-vacuum chamber that allows us to expose the surface of interest to gases from three independent molecular beams. Reactions at the surface, and the energy, angular distribution, and identity of any scattered or desorbed atom or molecule can be determined. Recently, we have been studying the properties of self-assembled monolayer (SAM) surfaces. Of particular interest has been the energy exchange of impinging gas atoms as a function of incident energy and mass. This information is important for understanding aerodynamic drag and surface accommodation, an important first step in surface reactions. We have also been studying the reactions of atomic oxygen with these surfaces. As an important constituent of the outer reaches of the earth's atmosphere, understanding atomic oxygen reactions is important for improving the longevity of orbiting satellites.

Qiti Guo, Senior Research Associate

My research interests focus on the following. (1) Applications of Scanning Probing Microscopy (SPM) and Scanning Electron Microscopy (SEM) to materials research. (2) Application of photolithography and electron-beam lithography to materials research, with the emphasis on designing and fabrication of various micro electrico-mechanical system (MEMS) devices. (3) Thermochemistry of intermetallic compounds of transition metals and thermochemistry of mixed oxide systems, using a Kleppa type high-temperature reaction calorimeter. (4) Topological relations in systems of n + 3 and more than n+3 phases (n stands for the number of independent components of the systems). At the same time, being a senior research staff of the James Franck Institute and the Chicago Materials Research Center (MRSEC), I am in charge of the Materials Preparation Laboratory (MPL). It is my responsibility to teach students and other research staff the basics of some of the MRSEC shared facilities, including SEM and SPM (AFM and STM). I train people how to correctly operate these equipment, and also work with students to help them solve some experimental problems. I also teach students how to carry out photo- and e-beam lithographic experiment.