fast cooling down

Dear Steve,

Thank you for your response. I am using eam potential for modeling solid surface not argon. lj potential is used for argon.
type 1 is argon and type 2 is solid.

pair_coeff * * eam/alloy Pt.eam.alloy NULL Pt
pair_coeff 1 1 lj/cut 0.24035 3.4
pair_coeff 1 2 lj/cut 0.475 3.085

I would like to know whether the way I have used fixes and output temperature is correct for letting argon to cool down just due to its interaction with solid surface?
Thank you for your time.