UFF modification in Gaussian

Dear CCL subscribers:
 My name is Alex Le.  I'm trying to find a way to modify the UFF parameters to
 incorporate a new
 atom type.  I wonder if there is anyone who has been successfully at customizing
 the parameters in
 any software.  And if it is possible, would you please tell me the procedure?  I
 have tried to add
 the customized parameter at the end of a G03 input com file but still, there is
 something missing
 and the manual of G03 about the MM Force Field is not adequate in terms of
 explanation.
 I hope to receive some hints or suggestion soon.
 With best regards,
 Alex Le.
 Nhat Minh Le (Alex Le)
 Delta Chi - Brotherhood of a Lifetime
 nworld3d{at}yahoo.com
 www.247lfc.com | www.sr3d.net
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