[gmx-users] Re: charge groups

[Justin Lemkul]

On 11/6/12 6:56 AM, akn wrote:
> Dear Justin,
>
> Thank you for the answer.
>
> I'm using OPLS force field but I calculated the partial charges of the atoms
> from the HF geometry optimization.
>
> Do you have any idea if I should arrange the charge groups in this case or
> not?
>

My intuition says that a group-based approach is correct, not an atom-based 
assignment.  Parameterization of the OPLS-AA force field was done using model 
compounds that were then used as building blocks, so I believe that is where the 
multi-atom charge groups (as implemented in Gromacs) come from.

-Justin

-- 
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Justin A. Lemkul, Ph.D.
Research Scientist
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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