Ionicity and static ionic charge

Recently, Falter et al. have proposed an ionicity scale basing on the longitudinal effective charge e/sub L/ (that is wrongly identified with the static ionic charge q). It is shown that ionicities that vary linearly with q or e/sub L/ are, however, not appropriate to construct structural maps, and it is concluded that nor q, nor e/sub L/ is very relevant or even a measure for structural properties. (author)