A range of sodalites of general formula LiNa(AlSiO)Cl have been synthesised by structure conversion and ion exchange reactions. High resolution Si NMR spectra of these compounds demonstrate a single resonance, the frequency of which varies smoothly with lithium content and the geometry of the Si-(OAl) tetrahedron determined by powder neutron diffraction. Incorporation of lithium in the sodalite structure results in contraction of the Si-O-Al bond angle to accommodate the preferred coordination geometry of the smaller cavity species. In partially exchanged materials the chloride ion is displaced away from the cavity centre.
|Journal||Solid State Ionics|
|Issue number||PART 1|
|Publication status||Published - 1989|