MCPB.py, a python based metal center parameter builder, has been developed to build force fields for the simulation of metal complexes employing the bonded model approach.

Pengfei Li and Kenneth M. Merz, Jr., "MCPB.py: A Python Based Metal Center Parameter Builder." J. Chem. Inf. Model., 2016, Accepted, DOI.

There is an excellent and very detailed online page describing the use of MCPB.py http://ambermd.org/tutorials/advanced/tutorial20/mcpbpy.htm.