Two Unusual Layer Aluminophosphates Templated by Imidazolium Ions; [N₂C₃H₅][AlP₂O₈H ₂·2H₂O] and 2[N₂C₃H₅][Al₃P₄O ₁₆H]

Two new aluminophosphates [ImH][AlP₂O₈H₂·2H₂O] 1 and 2[ImH][Al₃P₄O₁₆H] 2 have been synthesized solvothermally at 160°C. Both compounds represent totally new structure types for the already extensive [AlP₂O₈] and [Al₃P₄O₁₆] families. Compound 1 has a simple, puckered 2-D sheet structure containing Al₄P₄8-membered rings and octahedral Al centers which are hydrated bytransaqua ligands. It is monoclinic, space groupC2/c,a=21.854(4),b=7.188(2),c=6.990(2) Å,β=103.77(2)°,V=1063.5(5) Å. Single crystal structure analysis gaveR=0.038,R_w=0.040 for 943 reflection intensities. Compound 2 has a complex layer structure which contains double 6MR subunits, the building blocks of many 3-D ALPOs, and has 5-coordinate as well as 4-coordinate aluminum. Single crystal structure analysis of 2 indicated the triclinic system, space groupP-1,a=8.940(2),b=9.360(2),c=11.721(2) Å,α=97.10(2)°,β=95.10(2)°,γ=91.91(2)°,V=968. 4(3) Å. Refinement gaveR=0.044,R_w=0.040 for 1613 unique observed reflections. © 1998 Academic Press