Avian Freeware Suite (AFS) provides two things: Developers with libraries for Java Swing Widgets, XML handling, Fortran95 and Pascal; End users (Medical students, doctors, scientists) with productivity tools they can use (quizzes, XML databasing & PDF)
The program fuses 2 sets of molecules. It tries different relative positions of molecules before binding them, so that there is no or minimal intersection in the resulting molecule. The atom to be fused in a molecule is labeled with an R symbol.