Next-near-neighbour interactions with Al in Li+- and Rb+-exchanged Na+ (beta)-aluminas, detected by synchrotron X-ray absorption spectroscopy

Synchrotron X-ray absorption near-edge structure (XANES) spectroscopy studies have been carried out on the electronic and crystal structure environments of the Al atom in Na+ (beta)-alumina and in two (beta)-aluminas with Na+ exchanged by Li+ and Rb+. The aim is to define the type of interaction, if any, existing between the Al located in the `spinel blockʹ and the fast-conducting cations in the `conduction planeʹ.