 Subsequent models of molecular structure yielded much better agreement with experiment when electron density was “allowed” to leave the area between the atoms and delocalize throughout the molecule. As the models were further improved, bonding came to be seen as a whole-molecule, not sub-molecular, phenomenon. Weisberg argues that such considerations should lead us to reject the structural conception of bonding and replace it with a molecule-wide conception. One possibility is the energetic conception of bonding that says that bonding is the energetic stabilization of molecules. Strictly speaking, according to this view, chemical bonds do not exist; bonding is real, bonds are not (Weisberg 2008; also see Coulson 1952, 1960).