However, because quantum mechanical calculations are carried out throughout Monte Carlo or molecular dynamics simulations, these calculations can be computationally demanding. Performance obtained to date has been encouraging. With the current parallel code, that time would be decreased directly dependent to the number of processors available. A contour plot of electron density in the plane of the newly forming carbon-carbon bonds is superimposed on the molecular framework of the two reacting molecules. A surface plot showing the electrostatic potential of the complex is also displayed.
Red areas indicate regions of negative charge while blue regions indicate positive charge.
Note the large region of negative charge associated with the oxygen atom of the ketone. This charge is stabilized by hydrogen-bond formation with the surrounding water molecules. Other applications to environmental problems are being considered in collaboration with Dr. Rabinowitz of the Environmental Protection Agency . This method has linear scaling of computational effort with respect to the size of molecules and is ideally suited for parallel execution. Molecular modeling based on quantum mechanical methods can provide structural information including the formation and breaking of chemical bonds, has general applicability, and is free of empirical parameters.