Search

Two open-framework germanates, SUT-1 and SUT-2, have been synthesized under hydrothermal conditions using ethylenediamine (en, H2NCH2CH2NH2) as templates and Ni(NO3)2·6H2O as the transition-metal source. Their frameworks are built with Ge10 clusters and [Ni(en)2]2+ complexes. In both structures, Ge10 clusters form square nets in the a–c plane, while the [Ni(en)2]2+ complexes bridge the square nets via Ni–O–Ge bonds to form 3D networks. They present the first examples to incorporate Ni2+ complexes into the germanate frameworks. In SUT-2, additional linkages by Ge2O7 clusters between the square nets generate a new type of topology.

The first layered iron borate, Fe5O5[B6O10(OH)3]·nH2O, has been prepared by the boric acid flux method. Its structure, determined by single crystal X-ray diffraction, contains a double FeO6-octahedral layer and an unusual [B6O13] chain. The rigid and cambered [B6O13] chains bend the octahedral layers, resulting in a wave-like and sandwiched structure. Crystallographic study indicates the structural modulation is mainly from the [B6O13] chains because of the insertion of water molecules in between. Nevertheless, FeO6 layers in the average structure, which are well separated by borate chains, is still a reasonable model to understand the two-dimensional magnetism. The strong antiferromagnetic interactions and the complex Fe3+-net suggest a possible geometrically magnetic frustration, which may be the reason for the second-order temperature-induced magnetic transition at 125 K. The condensed Fe3+ layers and the relatively low redox potential at about 1.25 V versus Li+/Li show its potentials as an anodic material.

We report a new open-framework silicogermanate SU-61 containing 26-ring channels with a low framework density. It can be seen as a crystalline analogue to the mesoporous silica MCM-41. The structur ...

A new three-dimensional open-framework aluminogermanate (denoted as SU-46) was synthesized solvothermally in a quasi nonaqueous media using diethylenetriamine (DETA) as the structure-directing agent. SU-46 was characterized by in situ X-ray powder diffraction (XRPD), infrared spectroscopy (FTIR), energy dispersive spectroscopy (EDS) on scanning and transmission electron microscopes, elemental analysis, and thermogravimetric analysis (TGA). The structure of SU-46 was determined by single-crystal X-ray diffraction. SU-46 is isostructural to the gallogermanate UCSB-9GaGe, having a new zeolite-framework structure built up by the secondary building unit 4=1. The structure is formed by vertex-sharing AlO4 and GeO4 tetrahedra and contains intersecting 8-ring channels in three different directions. The framework density of SU-46 is very low, 13.8 T atom/1000 A3. SU-46 is built from layers containing 3- and 9-rings. The building layer is compared to similar layers found in several pure germanates, borogermanates, ...