Dear Niall Jackson
Thank you for your reply,
Usually, C12 = A and C6 = B, but whichever paper you’re using should
make the form of the potential clear.
If C6 = B = 0, then you’re not using the Lennard Jones potential, you’re
using a 1/r**12 purely repulsive potential.
Now, But as you said I can not calculate the epsilon and sigma,