Energy-Based Molecular Fragmentation Methods

A major objective of theoretical and computational chemistry is the calculation of the energy and properties of molecules, so that chemical reactivity and material properties can be understood from first principles. The most accurate methods available today, which directly solve this equation for molecules, can only be applied to a very small subset of chemical problems. One approach that deals with the poor scaling of quantum mechanical methods with system size is not to treat the entire system with quantum mechanical methods. Often one is not interested in a detailed and highly accurate quantum mechanical treatment of the entire system, but rather a selected much smaller region of the system, for example, an active site in an enzyme.