Identification of molecular reactive sites with an interactive volume rendering tool

A new molecular visualization tool is presented, EVolVis tan abbreviation of electronic volume visualizer). This software enables the user to interactively explore a molecule's electronic charge density for topological features. Using novel volume rendering techniques, the entire molecule can be probed without obstruction by opaque surfaces or preselection of specific orbitals or contours. Menus with sliding scales permit various ranges of the function of interest to be examined interactively. We have investigated the Laplacian of the electronic charge density calculated for several biomolecules that contain a variety of reactive sites: cisplatin, penamecillin and isomers of nitrogen bases from DNA, EVolVis is useful in identifying inner-shell features (cisplatin)l polar, nonpolar and aromatic regions (penamecillin), hydrogen-bonding sites of varying strength (nitrogen bases and penamecillin:) and other reactive sites (strained heterocycle in penamecillin).