Despite the extensive growth in the syntheses and applications of new crystalline silicate-based porous materials and related molecular sieves,1 the analogous germanate chemistry remains virtually undeveloped with only few open-frameworks reported.2 Given that the minimum M-O-M angles in germanates are typically smaller (120-135°) than in porous silicates (140-145°), the former offers greater opportunities for the formation of threemembered rings and cluster aggregates, which are essential to achieving far more open frameworks having a structural diversity yet unobserved in silicates and their substituted derivatives.3 Anticipating the rich chemistry promised by germanates, we have embarked on a program designed to further this area. We report here on the transformation of germanium dioxide into Ge7O14.5F2‚ [(CH3)2NH2]3(H2O)0.86 (ASU-12) using largely nonaqueous soft chemical means.4 Its structure is constructed from Ge7 cluster units linked into a 3D porous net having intersecting channels where (CH3)2NH2 + (DMA+) and H2O guests reside. We have demonstrated that DMA+ can be reversibly exchanged for Na+ with full retention of the integrity and periodicity of the germanate open framework structure.