Synthesis of open-framework iron phosphates, [C5N2H14]2[Fe2IIIF2(HPO4)4]•2H2O and [C5N2H14][Fe4III (H2O)4F2(PO4)4], with one- and three-dimensional structures

The hydrothermal syntheses and structures of two new open-framework iron phosphates, [C5N2H14](2)[(Fe2F2)-F-III(HPO4)(4)] (.) 2H(2)O, I, and [C5N2H14][Fe-4(III)(H2O)(4)F-2(PO4)(4)], II, are presented. While the structure of I consist of FeO4F2 octahedra and HPO4 terahedra linked to form one-dimensional structure, that of II consist of FeO4(H2O)(2), FeO4(H2O)(2), FeO4F2 and PO4 units connected to give rise to a three-dimensional structure. The structure of I resembles the naturally occurring mineral tancoite while 11 resembles the iron phosphate, ULM-12, [C6N2H14][Fe-4(PO4)(2)F-2(H2O)(3)]. Magnetic susceptibility studies indicate anti-ferromagnetic behavior in both the compounds with T-N-200 and 175K for I and II, respectively. Crystal data: I, monoclinic, space group-P2(1)/n (no. 14). a = 7.2261(6) b = 16.5731(14), c = 11.0847(10) Angstrom, beta = 97.265(2)degrees, V = 1316.8(2) Angstrom(3), Z = 41, rho(calc) = 1.952g cm(-1), mu((MoKa)) = 1.446mm(-1), R-1 = 0.0448 and wR(2) = 0.1141 for 1882 data [I>2sigma(I)]; for II, monoclinic, space group = P2(1)/n (no. 14). a = 9.9691(3) b = 12.4013(3), c = 17.3410(3) Angstrom, beta = 103.762(1)degrees, V = 2082.32(9) Angstrom(3), Z = 4, rho(calc) = 2.576g cm(-1), mu((MoKalpha)) = 3.162 mm(-1), R-1 = 0.0510 and wR(2) = 0.1064 for 2979 data [I > 2sigma(I)]. (C) 2003 Elsevier Inc. All rights reserved.