Xenon vdw parameters

Hi all
 Does anyone out there know (or where I can find)
 CHARMM van der Waals parameters for Xenon?
 My par_all22_all.inp file has parameters for He
 and Ne, but no Xe.
 Thanks in advance,
 Richard L. Wood, Ph. D.
 Physical/Computational Chemist
 Post-doctoral Associate
 Department of Food Science
 120 Stocking Hall
 Cornell University, Ithaca, NY 14853