Crystal structure of imidazolium trialuminium dodecaoxotriphosphate monohydroxide, [C3H5N2][Al3P3O12(OH)], AlPO4-21

Abstract

C 3 H 6 Al 3 N 2 O 13 P 3 ,monoclinic, P12 1 /n1(no. 14), a =8.6191(4) Å, b =17.803(1) Å, c =9.0257(5) Å, b =107.357(2)°, V =1321.9 Å 3 , Z =4,Rgt(F) =0. Experimental detailsThe structural refinement was carried out by using the framework positions reported [2]. Anisotropic analysis for the framework atoms was employed. Following the discussion of av ariety of AlPO 4-21 structures, we assume that O1 represents ah ydroxyl group which links two trigonal bipramidal coordination polyhedra around Al1 and Al2. The possible hydrogen position of H1 was placed by the difference Fourier calculation and an isotropic temperature factor, U iso(H) =1.2 Ueq(O1) was employed. During the refinement of the inorganic framework structure, nonhydrogen atoms of occluded imidazole molecules were also found in difference Fourier maps and could be located in the channel. The imidazole molecules were suggested to be protonated so as to maintain the charge balance of the title compound. Several least-squares calculations indicated that imidazole molecules were disordered on two overlapping positions and the present analysis fixed the occupation of 50 %f or each position. Hydrogen atom attached to Ca nd Nw ere positioned geometrically and refined using ariding model (d(C-H) =0.93 Å, d(N-H) =0.86 Å and (U iso(H) =1.2 Uiso (C,N)).