<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 interested in simulating a anionic molecule BF4(-) ( Boron tetrafluoride). In the paper which developed the parameters for this molecule, it is mentioned that it has been used as 'rigid' molecule i.e the molecule only has non-bonding interaction but there was no intramolecular motion as the geometry was fixed.</div><div> I am trying to simulate this molecule in gromacs treating it as rigid. But, I was looking for best way to 'rigidify' this molecule.</div><div><br></div><div>I was wondering whether using LINCS to constrain all B-F and F-F bonds will be good enough . Or, Should I use virtual sites ? If I really need to use virtual site, will it be something like TIP5P water model ?</div><div> </div><div>Can someone suggest
the best wayout ?</div><div><br></div><div>Sanku</div><div> </div><div style="position:fixed"></div>
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