On Mon, Dec 29, 2014, Rebeca García Fandiño wrote:
> I am trying to parameterize a ligand using
> Antechamber (included in Ambertools). When I use amber11 there is no
> problem, but with Amber14, I got convergence problems:
Older versions of amber had much looser convergence criteria. We tightened
things up so that different computers (and compilers) would give answers
that were closer to each other.
See Note #6 on p. 268 of the Amber14 Reference Manual for more information.
>
>
> QMMM: No convergence in SCF after 1000 steps.
> QMMM: E = -0.4533E+07 DeltaE = -0.4975E-09 DeltaP = 0.7039E-13
> QMMM: Smallest DeltaE = 0.1737E-09 DeltaP = 0.6051E-07 Step = 105
It looks like you are very close to convergence, so loosening the convergence
criteria a bit may indeed help.
> Is there any way to decrease the convergence criteria in sqm but directly
> from the line $AMBERHOME/bin/antechamber -i ligand.pdb -fi pdb -o
> ligand.mol2 -fo mol2 -c bcc -s 2 -nc 0?
You can use the "-ek" flag to antechamber to do this.
...dac
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Received on Mon Dec 29 2014 - 18:30:02 PST
