IAtomContainerSet moleculeSet = chemModel.getMoleculeSet();
if (moleculeSet == null) {
moleculeSet = chemModel.getBuilder().newInstance(IAtomContainerSet.class);
chemModel.setMoleculeSet(moleculeSet);
}
moleculeSet.addAtomContainer(atomCon);
}
// The AtomPlacer generates coordinates for the new atom
AtomPlacer atomPlacer = new AtomPlacer();
atomPlacer.setMolecule(chemModel.getBuilder().newInstance(IAtomContainer.class,atomCon));