[gmx-users] CG to FG transformation error

[Martti Louhivuori]

On 21 Jan 2011, at 14:47, Anirban Ghosh wrote:
> I am trying to convert a coarse grained protein to a full atom model  
> after CGMD. I am using the modified gromacs_reverse code available  
> from MARTINI site. I am using the following command:
>
> g_fg2cg -pfg topol_fg.top -pcg pro_cg.top -n 0 -c pro_cg.gro -o  
> full.gro
>
> But in the output full.gro all the atoms are having coordinate  
> values as "0.00".
>
> My pro_cg.top file looks like:
>
> #define _FF_GROMOS96
> #define _FF_GROMOS42A2
> ;#define _FF_GROMACS
> ;#define _FF_GROMACS1
>
> [ defaults ]
> ; nbfunc        comb-rule       gen-pairs       fudgeLJ fudgeQQ
>   1                       1               yes             0.125   0.5
>
>
> #include "ffG43a2nb.itp"
> #include "ffG43a2bon.itp"
>
>
> Is this correct? where I am going wrong? I think the problem is with  
> pro_cg.top file only.

No. The problem is indeed your pro_cg.top. It should be a *CG  
topology* (like what you've used for the CG simulations), not an  
*atomistic FF*.

-martti-
--
Post-doctoral research fellow
Moleculaire Dynamica
University of Groningen
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