My research studies have always been near the borderline of theory and experiment and have always centered on puzzling problems of molecular structure and the chemical consequences of that structure. I worked for quite a few years with microwave spectroscopy when that technique was new. In recent years, my work has been completely theoretical but with strong connections with experimental groups, particularly in various fields of spectroscopy.

Our work in Austin is currently concerned with accurate ab initio studies with large basis sets and a high level of correlation treatment for small molecular species, mostly radicals that are important in atmospheric and combustion chemistry. At the moment we are working on variational calculations of the completely anharmonic vibrational levels of radicals with multiple minima in their potential function. Getting the vibrational level distribution right is important in determining the thermodynamic properties of these radicals so that reaction rates can be calculated to build up atmospheric and combustion models. For radicals of the size that occur in such processes, the thermodynamic functions can be calculated more accurately and reliably than they can be measured.

Other studies involve collaboration with microwave and infrared experimentalists to obtain the best possible combined experimental and theoretical equilibrium potentials for small molecules.