DGrid and Basin are programs developed by Dr. Miroslav Kohout. Those interested can contact Dr. Kohout by E-mail to obtain source files, makefile, and manuals for free.
DGrid is a separate program that computes the density, density gradient, density Laplacian, one-electron potential, and electron localization function (ELF) on an equidistant grid, starting from TAPE21. (Visit the ELF Homepage for detailed information on ELF.)
All properties can be calculated also for each orbital (or group) separately. Other density functions can easily be implemented. Besides a DGrid format, the program can already output the grid data in Biosym and Grace format. Other formats can be easily implemented.
Basin is a program for the analysis of the bonding situation based on the data grid file from DGrid. It determines basins in analogy to Bader’s approach [regions separated by a zero flux surface in the gradient of the analyzed property (for instance the density, ELF, one-electron potential, etc.)] and computes the volumes of the basins as well as charge or the integral of other properties over the volumes.