/usr/include/freefoam/potential/ is in libfreefoam-dev 0.1.0+dfsg+1-3.
This file is owned by root:root, with mode 0o755.
..
/usr/include/freefoam/potential/azizChen.H
/usr/include/freefoam/potential/coulomb.H
/usr/include/freefoam/potential/dampedCoulomb.H
/usr/include/freefoam/potential/doubleSigmoid.H
/usr/include/freefoam/potential/electrostaticPotential.H
/usr/include/freefoam/potential/energyScalingFunction.H
/usr/include/freefoam/potential/exponentialRepulsion.H
/usr/include/freefoam/potential/harmonicSpring.H
/usr/include/freefoam/potential/lennardJones.H
/usr/include/freefoam/potential/maitlandSmith.H
/usr/include/freefoam/potential/noInteraction.H
/usr/include/freefoam/potential/noScaling.H
/usr/include/freefoam/potential/pairPotential.H
/usr/include/freefoam/potential/pairPotentialI.H
/usr/include/freefoam/potential/pairPotentialList.H
/usr/include/freefoam/potential/pairPotentialListI.H
/usr/include/freefoam/potential/pitchForkRing.H
/usr/include/freefoam/potential/potential.H
/usr/include/freefoam/potential/potentialI.H
/usr/include/freefoam/potential/restrainedHarmonicSpring.H
/usr/include/freefoam/potential/shifted.H
/usr/include/freefoam/potential/shiftedForce.H
/usr/include/freefoam/potential/sigmoid.H
/usr/include/freefoam/potential/tetherPotential.H
/usr/include/freefoam/potential/tetherPotentialList.H
/usr/include/freefoam/potential/tetherPotentialListI.H