Thanks dear Amine

The problem I am facing with RGP file is that the solver diverges randomly even with time step as low as 1.0e-9  with errors mostly on 'fatal overflow in linear solver' and 'out of bound message for Cp'

It behaves well with Cubic equation of state and time step is also nice: 1.0e-7

That's why I wanted to know the parameter.

I am sorry I had to delete the post where I posted my mail id.  I got a threat message from some hacker...

Best regards