Theoretical and computational chemistry is based on a rigorous mathematical or simulational approach to problems of chemical, physical, or biological interest. The laws of nature-quantum or classical mechanics, electromagnetic theory, thermodynamics, and statistical mechanics-provide the foundation, while the tools range from pencil and paper to massively-parallel supercomputers. Current theoretical and computational research at UCI covers a broad range of topics, including methodology for quantum dynamics simulation, theoretical spectroscopy, femtochemistry, electronic structure, biomolecular structure and dynamics, atmospheric chemistry, nanotechnology, foundations of quantum mechanics and quantum information theory, and novel methods of signal processing.