Lennard-Jones thermodynamic integration example
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3D water box with an ion. Thermodynamic integration between different Lennard-Jones parameters, using U(l) = (1-l) U1 + l U2, using a linear combination of the Lennard-Jones parameters (only one force calculation is needed)
These calculations work only for this specific system and force field. For modifications other than parameters (ie number of ION atoms, force field type...), the python functions should be modified.
