How to use Feymann-Hibbs correction to Lennard-Jones?

[Cheng]

Hello,
       I am trying to calculate the adsorption of hydrogen molecular. In a lot of papers Feymann-Hibbs correction is used and I'm wondering how I can specify the input file in RASPA to use such correction? Is it some parameters in force_field.def or force_field_mixing_rule.def?
Thanks very much!