[gmx-users] control parameter on the Lennard-Jones interactions

[battistia at libero.it]

Dear gromacs members,

I would ask you if in gromacs is possible to add a control parameter on the Lennard-Jones interactions.
For example we have two atoms A and B and the corresponding parameters;  sigma(A), eps(A),  sigma(B), esp(B); then for the A-B interactions we have the parameters obtained with the Lorentz-Berthelot or with the geometrical average.

I would like to have a standard interaction between A or B with the other atoms of the system.  In the same time I would like to add a control parameter C on the interaction between A and B to have the following potential:
V(r(AB))=4*eps(AB)*[(sigma(AB)/r(AB))^(12)-C*(sigma(AB)/r(AB))^(6)]

Is it possible? How can I manage this calculation?


Many thanks,


Anna