<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:'times new roman', 'new york', times, serif;font-size:12pt"><div>Hi,</div><div> I am trying to write a topology in gromacs format for a recently developed molecule in OPLS format. From the parameterization-paper, I know the partial charges on each of the atom in that molecule from the corresponding paper . But, I am not sure how to split the molecule topology into several charge-groups. I mean, is there any thumb-rule on how to define opls charge groups for using in gromacs. Only thing I know from mailing list is that one should not use large charge-groups. But, I was wondering if someone can provide some input on how to define charge-groups.</div><div>Sanku</div><div style="position:fixed"></div>
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