[gmx-users] How are the charges of the gromos96 forcefiel calculated ?

[Justin Lemkul]

On 11/29/12 9:06 PM, Tanos Franca wrote:
>      Dear users,
>      I'm trying to find out how the atoms charges in the GROMOS96 force field
> were calculated but I've not been able to find out in the manual or in the paper
> I saw so far. I know that the force fields for MM have the atoms charges
> calculated by ab initio mathods but I wonder with method was used to GROMOS96.
> Was it B3LYP 6-31G* in the same way as for OPLSaa ?

The original methodology for Gromos87 and Gromos96 charge derivation is not 
publicly available, but is in the Gromos software manuals from what I 
understand.  I spoke with a member of their group recently and apparently some 
basic electron density calculations were done and then charges were fitted 
empirically until satisfactory results were achieved.  We published a paper a 
few years ago with some suggestions for more definable methodology using common 
programs: http://pubs.acs.org/doi/abs/10.1021/ci100335w.

-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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