[gmx-developers] More than one settle type

[Justin A. Lemkul]

Emanuel Birru wrote:
> Hi,
> 
>  
> 
> I am about to calculate partition coefficient of a water molecule using 
> gromacs 4.0.7 . To do the calculation I used spc water model as a 
> solvent and as a solute, I just changed the solute’s residue name and 
> use the same itp file as the spc.itp of gromacs with the name sol.itp. I 
> can manage to put them in a box as a solute and solvent, but the problem 
> arise when I start doing minimization. I tried to minimised using L-BFGS 
> and steep. The error message that I got is the following
> 
> “Fatal error:
> 
> More than one settle type.
> 
> Suggestion: change the least use settle constraints into 3 normal 
> constraints.”
> 
>  
> 
> You can get the minimization mdp (em1 and em2) files and my solute itp 
> file (sol) at the following link.
> 
> http://hydra.pharm.monash.edu.au/md_project/em1.txt
> 
> http://hydra.pharm.monash.edu.au/md_project/em2.txt
> 
> http://hydra.pharm.monash.edu.au/md_project/sol.txt
> 
>  
> 
> Could any one suggest a solution please.
> 

There are solutions in the list archive and in the error message itself.  You 
cannot have two separate blocks of molecules (water) that use SETTLE.  Use an 
equivalent [constraints] directive to mimic the effects of SETTLE, defining two 
O-H constraints and an H-H constraint.

-Justin

>  
> 
> Cheers,
> 
> Emanuel
> 

-- 
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Justin A. Lemkul
Ph.D. Candidate
ICTAS Doctoral Scholar
MILES-IGERT Trainee
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin

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