Michelle M. Francl

Associate Professor

Computational And Theoretical Physical Chemistry

Born, 1958. B.S., University of California, Irvine, 1979. Ph.D., University of California, Irvine, 1983. Postdoctoral research, Princeton University, 1983-1985.

Phone: (610)526-5108
e-mail: mfrancl@brynmawr.edu.
web page: www.brynmawr.edu/chemistry/mfrancl.html

Teaching Philosophies and Opportunities

In some ways, I want to know what make my students tick as much as I want to know what makes molecules tick. I hope students come away not just with a collection of facts, but with a whole picture that they can use to help organize and understand the world. To this end, I've been working to make my teaching more available to a wider range of students and to involve students in the material in multiple ways. My efforts on the latter have focused on two areas: active engagement in the lecture, and writing. Examples of some of this work are detailed below.

Nearly a decade ago I began incorporating writing into the general chemistry course. This began with a "project" where students had to solve an interesting (to them, not me) problem related to the course material, then present the problem and solution in a paper. Student projects ranged from explaining the chemistry in an African legend describing the preparation of indigo dye to what makes vanilla smell like vanilla. Students get experience with solving problems that are less pre-digested than those they usually encounter in this level course and the writing component gives me an additional assessment modality. After a presentation of this approach at a meeting, it was implemented by Professor Len Fine in the general chemistry course for engineers at Columbia. They have found it successful and have continued to employ it.

Over the past several years I have begun to change the nature of the physical chemistry lecture. Formal lectures have been replaced with directed work for about 1/3 to 1/2 of the course. In a related advanced course the lecture was completely replaced with a series of problems and exercises to be discussed by the students. Physical chemistry lecture exercises typically make use of the computer program Mathematica. Visualization of important mathematical relationships and numerical methods are emphasized. The advantages of such an approach include better comprehension of basic principles as well as an ability to tailor the material to the level of each student. Students are also introduced to numerical approaches to physical chemistry, something simply not possible with a blackboard approach. Two of the modules developed for this course are now available via MathSource (Numerical Approaches to Chemical Kinetics and Introduction to Statistical Mechanics).

My work in the College Seminar program addresses my desire to engage all students with science- regardless of major or career path. This course was designed to integrate the typical textual materials of a seminar course with the stuff of science - experiments. Working colleagues in other disciplines (English and Dance), I developed a set of laboratory experiments that integrated into the course readings and discussions and were accessible to any student at Bryn Mawr. For example, one such experiment involved reproducing Pasteur's crystallization of tartaric acid and the microscopic examination of the crystal forms. Students not only did the laboratory work, but read excerpts from Pasteur's own lab notebooks, as well as the scientific paper describing the work and his own descriptions of the work to a contemporary biographer. The goal of the course was not only to expose students to science as a discipline, but to help them see it in the context of humanities and social sciences.

A fellow in my group would have the opportunity to work with me in the integration of active learning methods into introductory or advanced courses and to work with me on the teaching of the pre-disciplinary College Seminar course.

Reseach Interests

My principal interest is in what makes molecules work at the fundamental level. My research area is broadly that of computational chemistry. I am active in both the development of methods for applying computational techniques to problems of interest in the chemical community, as well as in the application of computational methods to the solution of chemical problems. While most of my applications work has been in the area of molecular orbital theory, density functional methods are beginning to play a larger role in the work I do. My interest in methods development has mostly focussed on approaches to assessing the reactivity of molecules, though of late I have branched out to consider issues of structure matching.

My group has a long standing interest in the development of methods for assessing the reactivity of molecules, particularly methods for assigning charges to atoms in molecules. The CHELP [J. Comp. Chem. 8, 894-905 (1987)] method, and methods based on it developed by myself and others, are widely used not only by computational chemists, but by many organic and biochemists as well. These methods have been implemented in the widely used GAUSSIAN and Spartan program suites. Charges derived from CHELP and sister methods have been used to derive force fields in use by organic chemists and biochemists. Over the last several years, my group has worked on methods to improve the reliability of these charges [J. Comp. Chem. 17, 367-383 (1996) and Rev. in Computational Chem. 14, 1-31 (2000)].

My group is also interested in structures and reactivities of organic and orgaometallic molecules. Like their transition metal counterparts, organoaluminum compounds exhibit a wide and interesting variety of structures. They also catalyze many of the same fundamental organic transformations. Understanding the mechanisms by which these reactions proceed is critical to a chemist's ability to manipulate the path of the reaction. The potential energy surface for a reaction is the key to it's theoretical description. During a sabbatical in 1992-93, I spent time in Professor Laurie Butler's lab at the University of Chicago. Her research focuses on how molecules "choose" between different pathways on the same potential energy surface. Her work shows that pathways with low barriers can be "blocked" due to the quantum mechanical mixing with a surface above. While there, I developed a simple theoretical model and some appropriate code to implement it to help determine the critical gap between surfaces. The results gave a good qualitative description of the phenomenon [J. Chem. Phys. 99, 4479-4494 (1993)]. It is possible that such mixing of surfaces could explain the unusual reactivity of alkyl aluminum complexes with aromatic ketones. The NSF is currently funding my preliminary work on this question ["Polar versus Single Electron Transfer Mechanisms in Reactions with Alkylaluminum(III) Reagents"].