bool OEInvertCenter(OEMolBase &mol, const OEAtomBase *atom)
bool OEInvertCenter(OEMolBase &mol, const OEAtomBase *atom,
                    const OEAtomBase *ref1, const OEAtomBase *ref2)

These functions perform a geometric inversion around the atom passed as the second argument. The second overloaded function allows the reference atoms that are held fixed during the inversion to be specified as the third and fourth arguments. The functions return true if inversion completes successfully. The functions return false if the center is not either degree three or degree four, if the reference atoms are invalid, if the center to invert has more than two rings bonds, or if a geometric inversion is ill defined.

The molecule on which to perform inversion.
The atom around which to perform the geometric inverion.
The first reference atom to be held fixed.
The second reference atom to be held fixed.