 A generally acknowledged problem for the delocalized account is the lack of what chemists call transferability. Central to the structural view, as we saw, is the occurrence of functional groups common to different substances. Alcohols, for example, are characterized by having the hydroxyl OH group in common. This is reflected in the strong infra red absorption at 3600cm–1 being taken as a tell-tale sign of the OH group. But ab initio QM treatments just see different problems posed by different numbers of electrons, and fail to reflect that there are parts of a molecular structure, such as an OH group, which are transferable from one molecule to another, and which they may have in common (Woody 2000, 2012).