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Microporous vanadosilicate AM-6 has been hydrothermally synthesized for the first time in the absence of titanosilicate ETS-10 seeds. High purity (95–100% AM-6) products were crystallized under static conditions at 430–503K using tetramethylammonium hydroxide (TMAOH) or tetramethylammonium bromide (TMABr) as a structure-directing agent in mixtures with molar compositions xNa₂O:1.3K₂O:ySiO₂:0.5V₂O₅:wTMA:zH₂O, where x=4.5 or 5.6, y=4.3–5.5, w=2.0–3.0, and z=206–214. The size (∼250nm to ∼9μm range), truncated square bipyramidal morphology (varied from square cuboid to thin (thickness <100–200nm) tetragonal platy), and surface irregularities/faulting of AM-6 crystals (Si/V=5.0±0.5) can be controlled by varying the molar composition or initial pH of synthesis mixture, and crystallization temperature. Structure-directing agent can be removed from the pores with little or no adverse effects on …