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1.
Pseudo‐Isomerism by Different Jahn‐Teller Ordering: Crystal Structures of the Hemihydrate and the Monohydrate of (pyH)[MnF(H2PO4)(HPO4)] With pyridinium counter cations (pyH+) the MnIII fluoride phosphate anion [MnF(H2PO4)(HPO4)] can be stabilized. It forms a chain structure with Mn3+ ions bridged by a fluoride ion and two bidentate phosphate groups. Under sleightly differing conditions either the hemihydrate (pyH)[MnF(H2PO4)(HPO4)]·0.5H2O ( 1 ) or the monohydrate (pyH)[MnF(H2PO4)(HPO4)]·H2O ( 2 ) is formed. The hemihydrate 1 crystallizes monoclinic in space group P21/n, Z = 8, a = 7.295(1), b = 17.052(2), c = 18.512(3) Å, β = 100.78(1)°, R = 0.033, the monohydrate triclinic in space group P1¯, Z = 2, a = 7.374(1), b = 8.628(1), c = 10.329(1) Å, α = 83.658(8)°, β = 77.833(9)°, γ = 68.544(8)°, R = 0.025. Whereas the topology of the chain anions is identical in both structures, the Jahn‐Teller effect is expressed in different ordering patterns: in 1 antiferrodistortive ordering of [MnF2O4] octahedra is observed, with alternating elongation of an F—Mn—F‐axis or a O—Mn—O‐axis, respectively. This leads to asymmetrical Mn—F—Mn‐bridges. In 2 ferrodistortive ordering is found, with elongation of all octahedra along the F—Mn—F‐axis. Thus, symmetrical bridges are formed with long Mn—F distances. This unusual pseudo‐isomerism is attributed to the differing influence of inter‐chain hydrogen bonds.  相似文献   

2.
《Microporous Materials》1997,8(3-4):103-112
Fe4F3(PO4)(HPO4)4(H2O)4(N2C3H12) (labelled ULM-15) was prepared hydrothermally (7 days, 453 K, autogenous pressure) in the presence of 1,3-diaminopropane as organic template. Its structure was determined by single crystal X-ray diffraction. ULM-15 is monoclinic (Space group C2/c (no 15)) with lattice parameters a = 24.176(1) , b = 14.558(1) , c = 7.186(1) , β = 102.3(1)°, V = 2470.8(3) 3, Z = 4. Its three-dimensional framework is constituted from corner-sharing FeX6 (X = O, F, H2O) octahedra and tetrahedral PO4 and HPO4 groups. The structure presents trans-chains of FeO4F2 octahedra related to ferric dimers [Fe2O8F2(H2O)2] by tetrahedral units. They delimit 16-membered rings channels along [001] in which the diprotonated amines are inserted. ULM-15 shows 3D antiferromagnetic behaviour below TN ≈ 22 K.  相似文献   

3.
Dicaesium divanadium trioxide phosphate hydrogenphosphate, Cs2V2O3(PO4)(HPO4), (I), and dicaesium tris[oxidovanadate(IV)] hydrogenphosphate dihydrate, Cs2[(VO)3(HPO4)4(H2O)]·H2O, (II), crystallize in the monoclinic system with all atoms in general positions. The structures of the two compounds are built up from VO6 octahedra and PO4 tetrahedra. In (I), infinite chains of corner‐sharing VO6 octahedra are connected to V2O10 dimers by phosphate and hydrogenphosphate groups, while in (II) three vanadium octahedra share vertices leading to V3O15(H2O) trimers separated by hydrogenphosphate groups. Both structures show three‐dimensional frameworks with tunnels in which Cs+ cations are located.  相似文献   

4.
New compounds, Sr2Ga(HPO4)(PO4)F2 and Sr2Fe2(HPO4)(PO4)2F2, have been prepared by hydrothermal synthesis (700°C, 180 MPa, 24 h) and characterized by single-crystal X-ray diffraction. Sr2Ga(HPO4)(PO4)F2 crystallizes in the monoclinic space group P21/n with a = 8.257(1) Å, b = 7.205(1) Å, c = 13.596(2) Å, β = 108.02(1)°, V = 769.2(2) Å3 and Z = 4 and Sr2Fe2(HPO4)(PO4)2F2 in the triclinic space group P21/n with a = 8.072(1) Å, b = 8.794(1) Å, c = 8.885(1) Å, α = 102.46(1)°, β = 115.95(1)°, γ = 89.95(1)°, V = 550.6(1) Å3 and Z = 2. Structures are both based on different sheets involving corner-linkage between octahedra and tetrahedra. The sheets are linked by Sr2+ cations. Structural relationships exist between the descloizite mineral and the title compounds.  相似文献   

5.
The new ternary calcium indium(III) phosphate CaIn2(PO4)2(HPO4) with mixed octahedral-tetrahedral framework was synthesized through hydrothermal reaction of stoichiometric amounts of CaO and InCl3 with excess of H3PO4 and H2O at pH = 1. Single crystal x-ray diffraction studies show the compound to crystallize in monoclinic symmetry, space group P21/n (#14) with a = 657.08(6), b = 2023.7(2), c = 665.72(7) pm, β = 91.20(1)°, Z = 4 and R = 0.043. The framework is built up of dimers of edge-sharing InO6 octahedra forming In2O10 units sharing all their OXO ligands with PO4 tetrahedra, and HPO4 groups.  相似文献   

6.
Single crystals of potassium iron hydrogen phosphate, KFe3(HPO4)2(H2PO4)6 · 4 H2O, were prepared hydrothermally by heating a mixture of Fe2O3, H3PO4 and K2CO3 with a small amount of water. It crystallizes monoclinic, space group C2/c (N° 15 Int. Tab.) with Z = 4 and a = 1701(2), b = 960.4(5), c = 1750(1) pm, β = 90.88(7)°. The crystal structure was solved by using 1716 unique reflections F0 > 4σ(F0) with a final wR2 value of 0.126 (SHELXL-93). The main feature of the crystal structure are layers formed by PO4-tetrahedra around the FeO6-octahedra parallel to (001). K+ and H2O molecules connect these layers. Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR), Charge Distribution (CHARDI) and the Madelung Part of Lattice Energy (MAPLE) are calculated for the title compound. The existence of hydrogen bonds is confirmed by these calculations.  相似文献   

7.
Jahn‐Teller Ordering in pipzH2[Mn2F8], a Fluoromanganate(III) with a New Layer Structure From a solution of (pipzH2)[MnF2(HPO4)(H2O)]·(H2PO4) in concentrated hydrofluoric acid the title compound could be crystallized and was characterized by X‐ray crystallography: monoclinic, space group P21/n, Z = 8, a = 13.275(1), 10.400(1), c = 14.928(1) Å, β = 112.337(8), R = 0.0265. The structure shows a new type of anionic layers [Mn2F8] built of dimers of edge‐sharing [MnF6] octahedra linked via common vertices, alternating with layers of piperazinium(2+) cations. A dense network of hydrogen bonds N–H···F achieves a strong 3D interconnection. Strong elongation of the [MnF6] octahedra is observed due to the Jahn‐Teller effect.The long axes show parallel (ferrodistortive) orientation within the dimers, but the ordering between the dimers is antiferrodistorive. A possible mechanism of formation is discussed on the basis of precursor structures.  相似文献   

8.
The First Vanadium(III) Borophosphate: Synthesis and Crystal Structure of CsV3(H2O)2[B2P4O16(OH)4] CsV3(H2O)2[B2P4O16(OH)4] was prepared under mild hydrothermal conditions (T = 165 °C) from mixtures of CsOH(aq), VCl3, H3BO3, and H3PO4 (molar ratio 1 : 1 : 1 : 2). The crystal structure was determined by X‐ray single crystal methods (monoclinic; space group C2/m, No. 12): a = 958.82(15) pm, b = 1840.8(4) pm, c = 503.49(3) pm; β = 110.675(4)°; Z = 2. The anionic partial structure contains oligomeric units [BP2O8(OH)2]5–, which are built up by a central BO2(OH)2 tetrahedron and two PO4 tetrahedra sharing common corners. VIII is octahedrally coordinated by oxygen of adjacent phosphate tetrahedra and OH groups of borate tetrahedra as well as oxygen of phosphate tetrahedra and H2O molecules, respectively (coordination octahedra VO4(OH)2 and VO4(H2O)2). The oxidation state +3 for vanadium was confirmed by measurements of the magnetic susceptibility. The trimeric borophosphate groups are connected via vanadium centres to form layers with octahedra‐tetrahedra ring systems, which are likewise linked via VIII‐coordination octahedra. Overall, a three‐dimensional framework constructed from VO4(OH)2 and VO4(H2O)2 octahedra as well as BO2(OH)2 and PO4 tetrahedra results. The structure contains channels running along [001], which are occupied by Cs+ in a distorted octahedral coordination (CsO4(H2O)2).  相似文献   

9.
Pale rose single crystals of SrMn2(PO4)2 were obtained from a mixture of SrCl2 · 6 H2O, Mn(CH3COO)2, and (NH4)2HPO4 after thermal decomposition and finally melting at 1100 °C. The new crystal structure of strontium manganese orthophosphate [P‐1, Z = 4, a = 8.860(6) Å, b = 9.054(6) Å, c = 10.260(7) Å, α = 124.27(5)°, β = 90.23(5)°, γ = 90.26(6)°, 4220 independent reflections, R1 = 0.034, wR2 = 0.046] might be described as hexagonal close‐packing of phosphate groups. The octahedral, tetrahedral and trigonal‐bipyramidal voids within this [PO4] packing provide different positions for 8‐ and 10‐fold [SrOx] and distorted octahedral [MnO6] coordination according to a formulation Mn Mn Mn Sr (PO4)4. Single crystals of β′‐Mn3(PO4)2 (pale rose) were grown by chemical vapour transport (850 °C → 800 °C, P/I mixtures as transport agent). The unit cell of β′‐Mn3(PO4)2 [P21/c, Z = 12, a = 8.948(2) Å, b = 10.050(2) Å, c = 24.084(2) Å, β = 120.50°, 2953 independent reflections, R1 = 0.0314, wR2 = 0.095] contains 9 independent Mn2+. The reinvestigation of the crystal structure led to distinctly better agreement factors and significantly reduced standard deviations for the interatomic distances.  相似文献   

10.
Synthesis, Crystal Structure and Thermal Behaviour of Fluoroaluminates of the Composition (NH4)[M(H2O)6](AlF6) (M = Zn, Ni), [Zn(H2O)6][AlF5(H2O)], and (PyH)4[Al2F10] · 4 H2O Four new fluoroaluminates were obtained from fluoroacidic solutions of respective metal salts. The compounds of zinc ( I a : P21/c, a = 12.688(3), b = 6.554(1), c = 12.697(3) Å, β = 95.21(3)°, V = 1051.5(4) Å3, Z = 4) and nickel ( I b : P21/c, a = 12.685(3), b = 6.517(1), c = 12.664(2)Å, β = 94.55(2)°, V = 1043.6(4) Å3, Z = 4) are isotypic and represent a new structure type consisting of two different cations, NH4+ and [M(H2O)6]2+ and [AlF6]3–‐anions. [Zn(H2O)6][AlF5(H2O)] ( II : C2/m, a = 10.769(2), b = 13.747(3), c = 6.487(1)Å, β = 100.02(3)°, V = 945.7(3) Å3, Z = 4) is characterized by a H2O/F‐disorder in the [AlF5(H2O)]‐octahedra in two trans positions. In (PyH)4[Al2F10] · 4 H2O ( III : Cmc21, a = 15.035(3), b = 20.098(4), c = 12.750(4) Å, V = 5364(2) Å3, Z = 8), bioctahedral [Al2F10]4– anions have been found for the first time. The structures are described and discussed in comparison. The new compounds were used as precursors in order to obtain new AlF3‐phases. However, the thermal decomposition did not result in the formation of any new metastable AlF3‐phase. Instead, phase mixtures of either α‐AlF3 and β‐AlF3 or AlF3 and MF2 were obtained.  相似文献   

11.
Yellowish single crystals of acidic mercury(I) phosphate (Hg2)2(H2PO4)(PO4) were obtained at 200 °C under hydrothermal conditions in 32% HF from a starting complex of microcrystalline (Hg2)2P2O7. Refinement of single crystal data converged at a conventional residual R[F2 > 2σ(F2)] = 3.8% (C2/c, Z = 8, a = 9.597(2) Å, b = 12.673(2) Å, c = 7.976(1) Å, β = 110.91(1)°, V = 906.2(2) Å3, 1426 independent reflections > 2σ out of 4147 reflections, 66 variables). The crystal structure consists of Hg22+‐dumbbells and discrete phosphate groups H2PO4 and PO43–. The Hg22+ pairs are built of two crystallographically independent Hg atoms with a distance d(Hg1–Hg2) = 2.5240(6) Å. The oxygen coordination sphere around the mercury atoms is asymmetric with three O atoms for Hg1 and four O atoms for Hg2. The oxygen atoms belong to the different PO4 tetrahedra, which in case of H2PO4‐groups are connected by hydrogen bonding. Upon heating over 230 °C, (Hg2)2(H2PO4)(PO4) condenses to (Hg2)2P2O7, which in turn disproportionates at higher temperatures into Hg2P2O7 and elemental mercury.  相似文献   

12.
Synthesis and Crystal Structure of K2(HSO4)(H2PO4), K4(HSO4)3(H2PO4), and Na(HSO4)(H3PO4) Mixed hydrogen sulfate phosphates K2(HSO4)(H2PO4), K4(HSO4)3(H2PO4) and Na(HSO4)(H3PO4) were synthesized and characterized by X‐ray single crystal analysis. In case of K2(HSO4)(H2PO4) neutron powder diffraction was used additionally. For this compound an unknown supercell was found. According to X‐ray crystal structure analysis, the compounds have the following crystal data: K2(HSO4)(H2PO4) (T = 298 K), monoclinic, space group P 21/c, a = 11.150(4) Å, b = 7.371(2) Å, c = 9.436(3) Å, β = 92.29(3)°, V = 774.9(4) Å3, Z = 4, R1 = 0.039; K4(HSO4)3(H2PO4) (T = 298 K), triclinic, space group P 1, a = 7.217(8) Å, b = 7.521(9) Å, c = 7.574(8) Å, α = 71.52(1)°, β = 88.28(1)°, γ = 86.20(1)°, V = 389.1(8)Å3, Z = 1, R1 = 0.031; Na(HSO4)(H3PO4) (T = 298 K), monoclinic, space group P 21, a = 5.449(1) Å, b = 6.832(1) Å, c = 8.718(2) Å, β = 95.88(3)°, V = 322.8(1) Å3, Z = 2, R1 = 0,032. The metal atoms are coordinated by 8 or 9 oxygen atoms. The structure of K2(HSO4)(H2PO4) is characterized by hydrogen bonded chains of mixed HnS/PO4 tetrahedra. In the structure of K4(HSO4)3(H2PO4), there are dimers of HnS/PO4 tetrahedra, which are further connected to chains. Additional HSO4 tetrahedra are linked to these chains. In the structure of Na(HSO4)(H3PO4) the HSO4 tetrahedra and H3PO4 molecules form layers by hydrogen bonds.  相似文献   

13.
In the system ZnO/H3PO4/H2O/1,4‐diazacycloheptane (C5H12N2), a new zincophosphate (ZnPO), (C5H14N2)[Zn3(HPO4)4] ( I ), was prepared by hydrothermal transformation (180 °C) of the known ZnPO hydrate (C5H14N2)[Zn2(HPO4)3]·H2O ( II ). The thermally‐induced transformation is reversible; upon keeping the heterogeneous mixture of I and mother liquor at 80 °C recrystallization of II was observed. Single‐crystal X‐ray crystallography revealed that I possesses a unique three‐dimensional (3D) open‐framework structure built from corner‐linked ZnO4 and HPO4 tetrahedra. The (3,4)‐connected framework of I differs considerably from the 3D open‐framework ZnPO structure of II . Crystal data for I : Monoclinic system, space group Cc (No. 9) , Z = 4, a = 9.1389(6), b = 23.627(2), c = 9.3073(6) Å, β = 109.463(7)°, T = 298 K.  相似文献   

14.
Hydrothermally synthesized dipotassium gallium {hydrogen bis[hydrogenphosphate(V)]} difluoride, K2Ga[H(HPO4)2]F2, is isotypic with K2Fe[H(HPO4)2]F2. The main features of the structure are ([Ga{H(HPO4)2}F2]2−)n columns consisting of centrosymmetric Ga(F2O4) octahedra [average Ga—O = 1.966 (3) Å and Ga—F = 1.9076 (6) Å] stacked above two HPO4 tetrahedra [average P—O = 1.54 (2) Å] sharing two O‐atom vertices. The charge‐balancing seven‐coordinate K+ cations [average K—O,F = 2.76 (2) Å] lie in the intercolumn space, stabilizing a three‐dimensional structure. Strong [O...O = 2.4184 (11) Å] and medium [O...F = 2.6151 (10) Å] hydrogen bonds further reinforce the connections between adjacent columns.  相似文献   

15.
Single crystals of fluoride hydrates Mn3F8 · 12 H2O and AgMnF4 · 4 H2O have been prepared and characterized by X-ray methods. Mn3F8 · 12 H2O crystallizes in the space group P1 (a = 623.0(3), b = 896.7(4), c = 931.8(4) pm, α = 110.07(2)°, β = 103.18(2)°, γ = 107.54(2)°, Z = 1); AgMnF4 · 4 H2O crystallizes in the space group P21/m (a = 700.9(2), b = 726.1(1), c = 749.4(3) pm, β = 107.17(3)°, Z = 2). Both structures contain Jahn-Teller-distorted [Mn(H2O)2F4]? anions as well as crystal water molecules and exhibit a complex hydrogen bond network between anions and cations, i. e. [Mn(H2O)6]2+ for the first and a polymeric [Ag(H2O)2]? cation for the second compound.  相似文献   

16.
Structure and 1D‐magnetic properties of (pipzH2)[MnF4(H2PO4)] From hydrofluoric and phosphoric acid solution of Manganese(III), using piperazinium(2+) counter cations (pipzH22+) the chain‐anion [MnF4(H2PO4)]2— can be stabilized providing an interesting model system for studying the magnetic exchange interaction via phosphate bridges. Depending on the HF/H3PO4 excess (pipzH2)[MnF4(H2PO4)] crystallizes in two polymorphs I und II , differing mainly in the orientation of the cations. Form I is monoclinic, space group P21/c, Z = 4, a = 6.749(1), b = 12.039(1), c = 12.501(1) Å, β = 94.420(4)°, R = 0.023, Form II crystallizes in the same space group type P21/c, Z = 4, a = 6.651(1), b = 12.799(1), c = 12.825(1) Å, β = 110.312(5)°, R = 0.037. The Mn3+ ions are octahedrally surrounded by four terminal fluoride ligands and axially by bidentate bridging dihydrogenphosphate groups. The shape of the chain anions is very close in both modifications and characteristic for ferrodistortive Jahn‐Teller ordering.The Mn—O‐bonds along the chain direction are strongly elongated (distances 2.16 to 2.21 Å) whereas all Mn—F bond (1.81—1.88Å) are ruther short. On a large single crystal of form I 1D‐antiferromagnetic properties were found. By fitting an appropriate model based on the temperature dependence of the correlation lengths using an anisotropy constant D/k = —2.9 K a remarkably high exchange energy of J/k = —1.6(1) K along the chains could be determined.  相似文献   

17.
Single crystals of sodium iron hydrogen phosphate, NaFe(HPO4)(H2PO4)2 · H2O, were prepared hydrothermally by heating a mixture of Fe2O3, H3PO4 and Na2CO3 with a small amount of water. It crystallizes orthorhombic (Pbcn (N° 60), Z = 8, a = 872.91(7), b = 1249.54(8), c = 1894.4(1) pm). The crystal structure was solved by using 1121 unique reflections I > 2σ(I) and refined for a final conventional residual R = 0.039 (188 variables, 25 atoms including hydrogen in the asymmetric unit). The main feature of the crystal structure is a ReO3-like network formed by hydrogenphosphate-, dihydrogenphosphate-groups and Fe O6 octahedra with channels along the [201], [010] and [201] directions. Na+ and H2O molecules are occupying these channels. Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR) and the Madelung Part of Lattice Energy (MAPLE) are calculated for the title compound.  相似文献   

18.
Synthesis of Copper and Silver Complexes with Pentadentate N,S and Hexadentate N,O Chelate Ligands – Characterization and Crystal Structures of {Cu2[C6H4(SO2)NC(O)]2(C5H5N)4}, {Cu2[C5H3N(CHNC6H4SCH3)2]2}(PF6)2, and {Ag[C5H3N(CHNC6H4SCH3)2]}PO2F2 In the course of the reaction of copper(II)-acetate monohydrate with 2,2′-bisbenzo[d][1,3]thiazolidyl in methanol the organic component is transformed to N,N′-bis-(2-thiophenyl)ethanediimine and subsequently oxidized to the N,N′-bis-(2-benzenesulfonyl)ethanediaciddiamide H4BBSED, which coordinates in its deprotonated form two Cu2+ ions. Crystallisation from pyridine/n-hexane yields [Cu2(BBSED)(py)4] · MeOH. It forms triclinic crystals with the space group P1 and a = 995.5(2) pm, b = 1076.1(3) pm, c = 1120.7(2) pm, α = 104.17(1)°, β = 105.28(1)°, γ = 113.10(1)° and Z = 1. In the centrosymmetrical dinuclear complex the copper ions are coordinated in a square-pyramidal arrangement by three nitrogen and two oxygen atoms. The Jahn-Teller effect causes an elongation of the axial bond by approximately 30 pm. The reactions of the pentadentate ligand 2,6-Bis-[(2- methylthiophenyl)-2-azaethenyl]pyridine BMTEP with salts of copper(I), copper(II) and silver(I) yield the complexes [CU2(BMTEP)2](PF6)2, [Cu(BMTEP)]X2 (X = BF, C1O) and [Ag(BMTEP)]X (X = PO2F, ClO). [Cu2(BMTEP)2](PF6)2 crystallizes from acetone/diisopropyl- ether in form of monoclinic crystals with the space group C2/c, and a = 1833.2(3) pm, b = 2267.30(14) pm, c = 1323.5(2) pm, β= 118.286(5)°, and 2 = 4. In the dinuclear complex cation with the symmetry C2 the copper ions are tetrahedrally coordinated by two bridging BMTEP ligands. The Cu? Cu distance of 278.3pm can be interpreted with weak Cu? Cu interactions which also manifest itself in a temperature independent paramagnetism of 0.45 B.M. The monomeric silver complex [Ag(BMTEP)]PO2F2 crystallizes from acetone/thf in the triclinic space group P1 with a = 768.7(3) pm, b = 1074.0(5) pm, c = 1356.8(5) pm, α = 99.52(2)°, β = 96.83(2)°, γ = 99.83(2)° and Z = 2. The central silver ion is coordinated by one sulfur and three nitrogen atoms of the ligand in a planar, semicircular arrangement. The bond lengths Ag? N = 240.4–261.7 and Ag? S = 257.2 pm are significantly elongated in comparison with single bonds.  相似文献   

19.
Novel Halogenochalcogeno(IV) Acids: [H3O(Benzo‐18‐Crown‐6)]2[Te2Br10] and [H5O2(Dibenzo‐24‐Crown‐8)]2[Te2Br10] Systematic studies on halogenochalcogeno(IV) acids containing tellurium and bromine led to the new crystalline phases [H3O(Benzo‐18‐Crown‐6)]2[Te2Br10] ( 1 ) and [H5O2(Dibenzo‐24‐Crown‐8)]2[Te2Br10] ( 2 ). The [Te2Br10]2‐ anions consists of two edge‐sharing distorted TeBr6 octahedra, the oxonium cations are stabilized by crownether. ( 1 ) crystallizes in the monoclinic space group P21/n with a = 14.520(5) Å, b = 22.259(6) Å, c = 16.053(5) Å, β = 97.76(3)° and Z = 4, whereas ( 2 ) crystallizes in the triclinic space group with a = 11.005(4) Å, b = 12.103(5) Å, c = 14.951(6) Å, α = 71.61(3)°, β = 69.17(3)°, γ = 68.40(3)° and Z = 1.  相似文献   

20.
A Fluoride Phosphate of Manganese(III) with Unusual Layer Structure: Na7[Mn5F13(PO4)3(H2O)3] The title compound was crystallized from a solution of MnF3 · 3 H2O in aqueous HF by addition of NaH2PO4 · H2O in 2 M phosphoric acid. The crystal structure has been determined at 295 and 150 K on a trigonal crystal twinned by merohedry: Space group P3c1, Z = 4, a = 1055,0(1), c = 2314,0(1) pm (a = 1052,5(1), c = 2304,2(1) pm at 150 K), wR2 = 0.0651 (0.0651). The structure contains anionic layers formed by triangular moieties of three [MnF3O2(H2O)] octahedra sharing one common μ3-F atom and bridged by three phosphate groups. Three of those groups, respectively, are interconnected by two [MnF3O3] octahedra over six phosphate O-atoms to form a trigonal layer in the a,b plane. Stacking of these layers gives channels along the c axis in which most of the Na+ ions are located. The [MnF3O2(H2O)] octahedra show strong elongation along the μ3-F–Mn–OH2 axis mainly due to the Jahn-Teller effect whereas in the [MnF3O3] octahedra with C3 symmetry weak signs only of a dynamical Jahn-Teller-effect can be observed. The magnetic properties (μeff = 4.61 μB, 3-D ordering point TN = 3.3 K) were determined on powders and possible magnetic exchange pathways are discussed.  相似文献   

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