Synthesis and single-crystal structure of a lithium aluminogermanate with the zeolite ABW topology

An aluminogermanate possessing the zeolite ABW framework topology has been synthesized hydrothermally from lithium-containing gel mixtures. This material, of composition LiAlGeO₄ · H₂O, has been structurally characterized by single-crystal X-ray diffraction. It has an orthorhombic unit cell with a = 10.610(2) Å, b = 8.300(2) Å, and c = 5.097(1) Å, and adopts space group Pna2₁, showing strict alternation of aluminum and germanium in the framework. The structural parameters are compared with those derived for other materials possessing the ABW topology. The germanium substitution in the framework leads to a larger unit-cell volume for AlGe-ABW compared with AlSi- and GaSi-ABW framework structures. (C) 2000 Elsevier Science B.V. All rights reserved.