CCL:G: Convergence of ruthenium nitrosyl complexes

[Ben Sattelle <ben.sattelle*|*postgrad.manchester.ac.uk>]

 Sent to CCL by: Ben Sattelle [ben.sattelle__postgrad.manchester.ac.uk]
 find good tips here ->
 http://www.ccl.net/cca/documents/dyoung/topics-orig/converge.html
 the book, Computational Chemistry: A Practical Guide ... is useful, ben.
> >  I have some problems of convergence in gaussian opt
> >  calculations for
> >  Ruthenium nitrosyl complexes. The problem began when
> >  I change a chlorine
> >  atoms in the sphere of coordination of ruthenium by
> >  nitrosyl molecules
> >  (NO). When I try to optimize the geometry of the
> >  complex (charge=+3 and
> >  multiplicity=1) by LanL2DZ or 3-21G* basis I always
> >  found that the
> >  criteria of convergence is not met???
> >  The error is the following:
> >  Restarting incremental Fock formation.
> >   Restarting incremental Fock formation.
> >   Restarting incremental Fock formation.
> >   >>>>>>>>>> Convergence criterion not met.
> >   SCF Done:  E(RHF) =  -6991.67598454     A.U. after
> >   65 cycles
> >               Convg  =    0.3086E-04             -V/T
> >  =  2.0035
> >               S**2   =   0.0000
> >   Convergence failure -- run terminated.
> >   Error termination via Lnk1e in //g98/l502.exe.
> >  thanks
> >  bye