The crystal structure was determined from powder diffraction data, and was refined by using the Rietveld technique. It was shown to be monoclinic, with a = 0.72155, b = 0.50214, c = 1.01380nm,  = 90.289, and space group: P21/c. It was isostructural with monoclinic Na2BeSiO4. The structure contained BeGeO42- layers which were formed from bi-nuclear Be2O6 groups which comprised 2 edge-sharing BeO4 tetrahedra. These, in turn, were interconnected by GeO4 tetrahedra. The Na atoms were located between the BeGeO42- layers and were octahedrally coordinated by O atoms. The ionic conductivity was determined by using impedance measurements, and was found to be equal to 6.7 x 10-6S/cm at 773K; with an activation energy of 0.82eV.

J.Grins: Journal of Solid State Chemistry, 1995, 118[1], 62-5