LAYERED STRUCTURES OF VANADIUM PENTOXIDE GELS

Layered structures of V2O5 gels, V2O5.n H2O, Were studied by means of the X-ray Rietveld method from a series of 00l reflections. The phases with 1.15-nm and 0.87nm layer spacings which appeared at room temperature and 260-degrees-C , respectively, were investigated. The 1-D Patterson maps suggested that a V2O5 layer consists of two V2O5 sheets facing each other at a distance of 0.28nm. The calculated patterns from this structure of a double-sheet V2O5 layer and bilayer arrangements of interstitial water fit to the observed ones for both phases and this structural type agreed well with the 1-D Fourier maps. The observed sample density confirmed the structure of double-sheet V2O5 layer. The 3-D structure of the V2O5 layer is proposed to be closely related to the structure of the V2O5 layer of delta-AgxV2O5.