Dear Prof Monard,
Many thanks for your quick response, still I am unable to find any
keyword that handles the optimizing process in sander. I went through the
manual bt I was unable to find such keyword. I will deeply appreciate you
if you help me to handle this process so that I can get proper QM
optimization.
Thanking you again.
On Fri, Jun 13, 2014 at 12:31 PM, Gerald Monard <
Gerald.Monard.univ-lorraine.fr> wrote:
> Hi,
>
> You cannot use the Gaussian optimizer since it is sander that masters
> what happens to the coordinates (from a coordinate set, sander asks
> gaussian to compute an energy, it does not let gaussian modify them,
> hence the "force" keyword).
> You'd better use one of the optimizers available in sander (&cntrl
> namelist) instead.
>
> Gerald.
>
>
> On 06/13/2014 11:16 AM, Kshatresh Dutta Dubey wrote:
> > Dear Users
> >
> > I am using Amber 14 for QM/MM calculation with Gaussian as external
> > interface. I have to optimize a system containing some amino acids and a
> > ligand in QM regions. I found that Amber automatically adds some keywords
> > in route section of Gaussian input that force Gaussian to do single point
> > calculations. For example, I used :
> > *&gau*
> > * mem = '2GB'*
> > *! method = 'B3LYP',*
> > *! basis = '6-31G',*
> > * use_template =1,*
> > * num_threads = 2*
> > * /*
> > for &gau namelist and :
> >
> > *#P OPT B3LYP/6-31G SCF=(Conver=8)*
> >
> > for template file namelist. The calculations runs fine and it shows
> normal
> > termination, but I found that it does only single point calculation not
> > optimizing the structure while I have mentioned optimization in route
> > sections. I notice that Amber adds some additional keyword such as
> 'Force'
> > in route section which restricts Gaussian to calculate forces only. I
> guess
> > it is fine for QM-MM/MD since we need forces for dynamics, but here I am
> > interested in QM/MM optimization only. The route section modified by
> Amber
> > is :
> >
> > *#P OPT B3LYP/6-31G SCF=(Conver=8) NoSymm Force Guess=Read Charge Prop=*
> > * (Field,Read)*
> >
> > How can I disable 'Force' keyword so that I can perform proper
> > optimization. I will be thankful for your help.
> >
> > thanks
> >
>
> --
>
> ____________________________________________________________________________
>
> Prof. Gerald MONARD
> SRSMC, Université de Lorraine, CNRS
> Boulevard des Aiguillettes B.P. 70239
> F-54506 Vandoeuvre-les-Nancy, FRANCE
>
> e-mail : Gerald.Monard.univ-lorraine.fr
> tel. : +33 (0)383.684.381
> fax : +33 (0)383.684.371
> web : http://www.monard.info
>
>
> ____________________________________________________________________________
>
>
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> http://lists.ambermd.org/mailman/listinfo/amber
>
--
With best regards
************************************************************************************************
Dr. Kshatresh Dutta Dubey
Post Doctoral Researcher,
c/o Prof Sason Shaik,
Hebrew University of Jerusalem, Israel
Jerusalem, Israel
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Received on Fri Jun 13 2014 - 03:00:02 PDT
