(C₄N₃H₁₅)[(BO₂) ₂(GeO₂)₄]: The first organically templated 3D borogermanate showing 1D 12-rings, large channels, and a novel zeolite-type framework topology constructed from Ge₈O₂₄ and B ₂O₇ cluster units

The first organically templated 3D borogermanate with a novel zeolite-type topology, (C₄N₃H₁₅)[(BO₂) ₂(GeO₂)₄] FJ-17, has been solvothermally synthesized and characterized by IR spectroscopy, powder X-ray diffraction (PXRD), TGA, and single-crystal X-ray diffraction. The compound crystallized in the monoclinic space group P2(1)/c with a = 6.967(1) Å, b= 10.500(1) A, c = 20.501-(1) Å, β = 90.500(3)°, V = 1499.68(8) ų, and Z = 4. The framework topology of this compound is the previously unknown topology with the vertex symbols 3·4·3· 9·3·8₂ (vertex 1), 3·8·3· 4·6₂·9₂ (vertex 2), 3·8 ₂·4·6₂·6₂·8 (vertex 3), 4·8·4·8·8₃·12 (vertex 4), 4·8·4·8·8₂·12 (vertex 5), and 3·8·4·6₂·6·8₂ (vertex 6). The structure is constructed from Ge₈O₂₄ and B ₂O₇ clusters. The Ge₈O₂₄ cluster contains eight GeO₄ tetrahedra that share vertices; the B ₂O₇ unit is composed of two BO₄ tetrahedra sharing a vertex. The cyclic Ge₈O₂₄ clusters connect to each other through vertices to form a 2D layer with 8,12-nets. The adjacent layers are further linked by the dimeric B₂O₇ cluster units, resulting in a 3D framework with 12- and 8-ring channels along the a and b axes, respectively. In addition, there is a unique B₂GeO ₉ 3-ring in the structure.