• From version 15.133 on, it is possible to assign different radii to
• The "constrain rotation" option can now constrain the angle of rotation
of all molecules of one type, so that they their centers are randomly
placed in space, but the molecules have an overall common orientation. This
can be used also to build lipid layers, for example, or maybe to build
• Packmol now prints the molecules in the same order that they were
setup in the input file.
• Constraints can be applied to a part of the molecules, in
such a way that molecules can be oriented in space. This is done by
using the atom selection.
• Thirteen different types of constraints allow you to build complex
starting configurations. The molecules (or some atoms within them) can
be placed inside or outside cubes, boxes, spheres, ellipsoids,
cylinders, over or below planes or can be fixed in a specified position.
• The function is now evaluated with an algorithm that scales
linearly with the number of atoms of the system: very large problems can
be solved in reasonable time.
• The powerful optimization algorithm GENCAN is now used as the
optimization subroutine providing greater speed and reliability (see The
TANGO Project link).
• The use of memory was optimized and now the only critical parameter
is the maximum number of atoms of the system.
• Much clearer code turns it possible for developers to change the
package to fit their needs.
Features that users want but we didn't have the time to implement.
• A graphical interface to VMD.
• Use periodic boundary conditions explicitly.
• Constrain the distance between molecules.
• Triclinical boxes and periodic conditions.