Synthesis and Characterization of a New Layered Fluoroaluminophosphate (C4H11 NOH)3.5[Al4(PO4)5F] ·0.5H3O with Extra-Large 16-Rings.

A new two-dimensional-layered fluoroaluminophosphate (C4H11NOH)3.5[Al4(PO4)5F]·0.5H3O (denoted as AIPO-CJ20) with an Al/P ratio of 4:5 has been synthesized solvothermally by using 2-amino-2-methyl-1-propanol as the structure-directing agent. Its structure was determined by single-crystal X-ray diffraction analysis and further characterized by solid-state NMR techniques, including 27Al, 19F → 27Al cross-polarization, and 31P magic angle spinning NMR. The alternation of Al-centered tetrahedra (AlO4 and AIO3F) and PO3(O) tetrahedra gives rise to a new type of 4.6.16-net sheet. The inorganic sheets are stacked in an ABAB sequence along the [010] direction and further held together through strong H bonds between protonated template molecules and PO groups in the inorganic layers. Except for Mu-4, AIPO-CJ20 is the second layered aluminophosphate with an Al/P ratio of 4:5, and it contains the largest pore opening of 16-rings in the known layered aluminophosphates. Furthermore, the coordination of Al and P of fluoroaluminophosphates is summarized. Crystal data: (C4H11 NOH)3.5[Al4(PO4)5F]·-0.5H3O, monoclinic, C2/c (No. 15), a = 32.678(7) Å, b = 12.956(3) Å, c = 21.045(4) &#00C5;, &#03B2; = 115.17(3)°, V = 8064(3) &#00C5;&#00B3;, Z = 8, R1 = 0.0837 [I &#003E; 2&#03C3;(I)], and wR2 = 0.2428 (all data). [ABSTRACT FROM AUTHOR]