An anionic framework aluminophosphate (CH₂)₆N₄H₃ · H₂O[Al₁₁P₁₂O₄₈] and computer simulation of the template positions

A new aluminophosphate compound (CH₂)₆N₄H₃ · H₂O [A1₁1_P12O₄8] (denoted AIPO-CJB2) with a three-dimensional open framework and an A1/P ratio of 11/12 has been synthesized solvothermally by using hexamethylenetetramine as a template. It was characterized by X-ray powder diffraction, inductively coupled plasma, elemental (CHN), and the thermogravimetric analyses, and the structure was determined by single-crystal X-ray diffraction analysis. AIPO-CJB2 crystallizes in the trigonal space group R-3c with a = 14.088(2) Å, c = 42.199(9) Å, and Z = 6. Its structure features two new kinds of cages, i.e., cage 1, 4¹24³6⁶8⁶ and cage 2, 4¹26¹2. The two cages alternate along the [0 0 1] direction forming an infinite column by sharing a common snowflake-like chiral motif, which is constructed from an AIO₆-centered six four-membered rings. The title compound is constructed from strictly alternating A1 polyhedra (AIO₄ and AIO₆) and P tetrahedra (PO₄) via bridging oxygen atoms, and presents a new type of stoichiometry with an A1/P ratio of 11/12 in the aluminophosphate family. Computer simulation was used to determine the possible positions of the organic template within the cages.