This API is currently available in C++ and Python.

double OEMMFFCalcVdw(const OEChem::OEMolBase &mol,
                     const OEChem::OEAtomBase *patom,
                     const OEChem::OEAtomBase *latom, bool coloumb=false,
                     bool attract=false)

This free function calculates the VdW/Coulomb interaction energy between a pair of atoms passed to the function as the second and third arguments, belonging to a molecule mol. Coulomb term is added to the result only when the fourth argument to the function is set true. A regular (not modified) MMFF VdW potential is used when the value of the last argument is set to true.