Combined Quantum Mechanical and Molecular Mechanical (QM/MM) Methods

"The underlying physical laws necessary for the mathematical theory of... the whole chemistry are thus completely known, and the difficulty is only that the exact application of these laws leads to equations much too complicated to be soluble." ------------ Dirac, 1929

"Only a small part of the system needs to be treated with Quantum Mechanics, the rest can be described at a more approximate level of theory (Classical Mechanics)" ------------ QM/MM Philosophers, Last Millennium

For more details, please see some of my past work and references there in.