Synthesis of open-framework iron phosphates (see abstract)

The hydrothermal syntheses and structures of two new open-framework iron phosphates, I, [C6N2H14][Fe2 III (HPO4)2(H2PO4)2] ·2H2O, II, and [C6N2H14]2[Fe3 III(OH)F3(PO4)(HPO4) 2]2·H2O, are presented. The structures of both I and II consist of FeO4F2 octahedra and PO4 terahedra linked to form one- and three-dimensional structures. Both the compounds possess infinite one-dimensional chains of Fe-O/F-Fe formed by the FeO4F2 octahedra. The di-protonated DABCO cations are located in between the chains in I and within the channels in II. Whilst I possess the tancoite structure with a new chain composition, II has a three-dimensional structure similar to the gallophosphate, ULM-1. Crystal data for I: M=685.84, monoclinic, space group = C2/c (no. 15), a = 7.232(2), b = 20.520(7), c = 13.933(4) Ã?, β = 97.68(3)°, ν = 2049.1(1) Ã?3, Z= 4, Ï?calc. = 2.223 g cm-3, μ(MoKα) = 1.841 mm-1, R1=0.06, wR2=0.12, S=1.17 for 163 parameters; II, M= 1303.33, monoclinic, space group = C2/c (no. 15), a= 18.1836(2), b = 10.0126(7), c = 20.0589(4) Ã?, β = 106.08(3)°, ν = 3509.0(2) Ã?3, Z=4, Ï?calc =2.467gcm-3, μ(MoKα)=2.830 mm-1, R1 = 0.034, wR2 = 0.081, S = 1.06 for 284 parameters. © 2002 Elsevier Science (USA).