Parameterise ligand with fluoride

Hi everyone.

I am planning to run a MD simulation for a protein-ligand system using the CHARMM forcefield. However, my ligand contains a fluoride and CGenFF is unable to provide parameters for it. Does this mean that I have to construct the parameters myself? If so, how do I achieve that?

Thank you all in advance for your help.

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GROMACS modification: Yes/No
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