MS21 Functional phosphate materials

5) A field dominated by the Al-rich phosphates, scorzalite- [4] Lin, C.H.; Yang, Y.C.; Chen, C.Y.,.Wang, S. L. Chem. Mater. lazulite, wardite, gordonite, jahnsite-whiteite, childrenite- 2006, 18, 2095-2101 eosphorite, souzalite-gormanite, variscite, augelite and [5] Lin, C. H.; Wang, S. L.; Lii, K. H. J. Amer. Chem. Soc. 2001, berlinite Al corresponding to high µH+ and low to 123, 4649. moderate µH2O conditions. 6) The more hydrated and oxidized portion of the MS21 P05 diagrams is composed by strengite, strunzite, Crystal structure and magnetic properties of + LiCr Fe P O diphosphates Hssain Bih, Ismael ferristrunzite, laueite and vivianite under higher µH y 1-y 2 7 Saadoune, Mohammed Mansori, Helmut Ehrenbergb and conditions. These group of more oxidized phases, also Hartmut Fuessb. aEquipe Chimie des Matériaux et de corresponds to the highest hydration stage. Heterosite and l’Environnement, LP2E2M, FST Marrakech, UCAM, tavorite are situated in the lower hydrated portion of all Morocco, bMaterial Science Department, TUD, Germany. diagrams and represent local dehydration process. The E-mail : [email protected] sequence of gradual increasing hydration strengite→strunzite→laueite or strengite→vivianite is relatively clear, and to certain broad extent heterosite→ Keywords : Rietveld Refinment, Phosphates, tavorite→strengite→ferristrunzite→laueite is also Magnetism obvious, according to the chemography. Vivianite During the past decade, research on positive electrode corresponds to the more hydrated and acid phosphate. materials for lithium batteries mainly focused on the Carbonates, siderite, rhodochrosite and sideroplesite, and layered oxides LiCoO and LiNiO , the spinel LiMn O , some arseniates, scorodite and pharmacosiderite, formed 2 2 2 4 and all their substituting derivative compounds. at the beginning of the oxidation process are relatively Nevertheless, polyanionic compounds built on PO widespread, even in small amounts. The last diagram 4 terahedra and MO octahedra (M: 3d element) deserve reflects a general tendency of the metasomatic alteration 6 special attention [1]. Efforts towards this relatively novel of the phosphate minerals, marked by the strong positive class of intercalation hosts focused on iron-containing slopes of the reactions, with successive destabilization systems. In order to compensate for the low intrinsic from the less to more hydrated phosphates, in terms of the electronic conductivity of this kind of sample, we develop chemical potentials considered. The large field dominated a ‘wet’ method based on mixing stoichiometric aqueous by the oxidic, basic and considerably hydrated phosphate, solutions of precursors followed by thermal treatment at cyrilovite defines and limits the paragenetic evolution low temperature compared to those used for classical together with vivianite and moraesite. It could also be solid state reactions. The solid solution series perceived that moraesite is the more hydrated phosphate of LiFe Cr P O was synthesized and their crystal the system. 1-y y 2 7 structures were refined using Fulprof program. In the

MS21 P04 whole composition range 0 ≤ y ≤ 1.0, a single phase, with Crystal Structures and Properties of Organically a colour depending on the chromium amount, was Templated Metal Phosphates and Metal Phosphites obtained. The XRD patterns exhibited very sharp peaks Sue-Lein Wang, Department of Chemistry, National and can be indexed in the monoclinic system (S.G. P21). Tsing Hua University. Hsinchu, Taiwan, ROC In the structure of these condensed phosphates, each MO6 E-mail: [email protected] (M: Fe1-yCry) octahedron is linked to five different P2O7 groups, one of them acting as a “chelating” sequence Keywords: Open-framework structure, zinc around the transition metal. These MP2O7 units are phosphate, zinc phosphite interconnected in a 3D network so as to create cavities in which lithium ions are located in a distorted tetrahedral Organic-inorganic hybrid metal phosphates have exhibited environment. Unit cell parameters of the end members of a variety of interesting open-framework structures as well this solid solution are: a = 4.8331(4) Å, b = 8.1006(6) Å, as a wide range of applications such the traditinal use in c = 6.9474(6) Å, β = 109.36(1)° for LiFeP2O7 and catalysis, gas sorption and ion exchange and modern a = 4.8125(7) Å, b = 8.0670(7) Å, c = 6.9158(8) Å, β = modern low-k materials, zeolite-dye micro-laser, or even 109.26(1)° for LiCrP2O7. Substitution of chromium for inorganic phosphor. Recently, we have investigated the iron leads to a continuous small decrease of the unit cell tetrahedral zinc phosphate materials and discovered parameters as a result of the difference in size between several phases with distinctive microporous structures and these two transition elements. Their valence state and the interesting photo luminescence property. Herein, we report magnetic interactions were determined by measuring the 3+ 3+ the NTHU-n series (n = 1-5) which include a neutral 24- thermal evolution of the magnetization. Fe and Cr 3+ 3 2 3+ 3 0 ring channel structure, a novel three-dimensional highly adopt their high spin configuration (Fe : t2 e ; Cr : t2 e porous organic-inorganic hybrid framework with bimodal ). LiFeP2O7 presents an antiferromagnetic behaviour porosity, an elastic layered lattice with capability of below 20 K with negative paramagnetic Curie molecular recognition by encapsulating supramolecular temperature ( p = -68 K). Similar results were obtained molecules, a unique mixed-metal zincophosphate with by G. Rousse et al. by studying this diphophate by intrinsic yellow/white emission, and the first 26-ring neutron diffraction [2]. The increase of the chromium channel structure of mixed metal phosphites. amount leads to decrease of the Fe-Fe strong antiferromagnetic interaction. [1] Liao, Y. C.; Lin, C. H.; Wang, S. L. J. Amer. Chem. Soc. 2005, 127, 9986. [1] Wurm C., et al., Chem. Mater., 2002, 14, 2701-10. [2] Liao, Y. C.; Jiang, C. J.; Wang, S. L. J. Amer. Chem. Soc. [2] Rousse G.,e t al., Solid State Ionics, 2002, 4, 973-78. 2005, 127, 12794. [3] Liao, Y. C., Liao, F.L., Chang, W.K., Wang, S.L. J. Amer. This work has been supported by the CNRST-DFG collaboration Chem. Soc, 2004, 126, 1320.

24th European Crystallographic Meeting, ECM24, Marrakech, 2007 Page s211 Acta Cryst. (2007). A63, s211