Which force filed to use with iodide ions in water

GROMACS version: 2019
GROMACS modification: No
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I’m going to observe iodide ions passing through an ion channel embedded in a large membrane. The CHARMM36 force field has been used for the protein and lipids.

But there is no iodide ion parameter in CHARMM36 force field. Do you know where or from which force filed can I get the proper iodide ion parameter for my simulation?

If the iodide parameter is given in another force field, can I incorporate it in my simulation while other parts with CHARMM36 ?

An research has employed the CHARMM Drude polarizable force field, providing a physically sound representation of the interaction between the highly polarizable iodide ion and the protein. Should I use this force field? ( But I think CHARMM36 is the best for an ion channel)

Thank you !