CCL: force calculation on mopac



 Sent to CCL by: "Gon  alo  Justino" [goncalo.justino*zmail.pt]
 Dear all,
 I recently upgraded to mopac 2002 built in ChemDraw for Windows. I'm trying to
 get a force calculation running but I'm stuck at this:
  - when I use AM1 GNORM=0.01 everything is ok, i get a nice output file;
  - when I use AM1 FORCE I get back  ** GRADIENT IS TOO LARGE TO ALLOW FORCE
 MATRIX TO BE CALCULATED, (LIMIT=10) ** EITHER ADD 'LET' OR REDUCE GRADIENT
 USING 'TS' OR OTHER GEOMETRY OPTIMIZER~
  - if I use AM1 FORCE TS, or AM1 FORCE LBFGS, I get back MORE THAN ONE GEOMETRY
 OPTION HAS BEEN SPECIFIED; CONFLICT MUST BE RESOLVED BEFORE JOB WILL RUN.
 This happens for any molecule. Is this my incompetence, software conflict or
 simple mis-installation?
 Any suggestion is welcome,
 Gonalo Justino
 goncalo.justino[a]zmail.pt