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1.
Jahn‐Teller Ordering in Manganese(III) Fluoride Sulphates. I. Crystal Structures of A2[MnF3(SO4)] (A = Rb, NH4, Cs) The three isostructural fluorosulphatomanganates(III) A2[MnF3(SO4)] (A = Rb, NH4, Cs) crystallize in space group P21/c, Z = 4. Rb2[MnF3(SO4)]: a = 7.271, b = 11.091, c = 8.776Å, β = 92.26°, R = 0.033; (NH4)2[MnF3(SO4)]: a = 7.299, b = 10.157, c = 8.813Å, β = 91.51°, R = 0.025; Cs2[MnF3(SO4)]: a = 7.365, b = 11.611, c = 9.211, β = 92.30°, R = 0.029. In the chain anions [MnF3(SO4)]2— manganese(III) is coordinated by two trans‐terminal and two trans‐bridging fluorine ligands, and by the O‐atoms of two briding sulphate ligands in trans position. The Jahn‐Teller effect induces a variety of antiferrodistortive ordering resulting in distorted [MnF4O2] octahedra with alternating elongation of F—Mn—F — and O—Mn—O — axes, respectively. Thus, only asymmetrical bridges are formed. 相似文献
2.
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
3.
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
4.
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
5.
Structure and Magnetic Properties of Bis{3‐amino‐1,2,4‐triazolium(1+)}pentafluoromanganate(III): (3‐atriazH)2[MnF5] The crystal structure of (3‐atriazH)2[MnF5], space group P1, Z = 4, a = 8.007(1) Å, b = 11.390(1) Å, c = 12.788(1) Å, α = 85.19(1)°, β = 71.81(1)°, γ = 73.87(1)°, R = 0.034, is built by octahedral trans‐chain anions [MnF5]2–∞ separated by the mono‐protonated organic amine cations. The [MnF6] octahedra are strongly elongated along the chain axis (<Mn–Fax> 2.135 Å, <Mn–Feq> 1.842 Å), mainly due to the Jahn‐Teller effect, the chains are kinked with an average bridge angle Mn–F–Mn = 139.3°. Below 66 K the compound shows 1D‐antiferromagnetism with an exchange energy of J/k = –10.8 K. 3D ordering is observed at TN = 9.0 K. In spite of the large inter‐chain separation of 8.2 Å a remarkable inter‐chain interaction with |J′/J| = 1.3 · 10–5 is observed, mediated probably by H‐bonds. That as well as the less favourable D/J ratio of 0.25 excludes the existence of a Haldene phase possible for Mn3+ (S = 2). 相似文献
6.
By adding piperazine to a hydrofluoric and phosphoric acid solution of Manganese(III) fluoride, the fluoride phosphate (pipzH2)[MnF2(HPO4)(H2O)](H2PO4) can be crystallized. Its structure is built by piperazinium(2+) cations, (H2PO4)? anions, and an anionic double‐chain of [HPO4] tetrahedra and [MnO3F2(H2O)] octahedra. The structure is triclinic, space group P , Z = 2, a = 622.97(4), b = 923.46(6), c = 1183.62(7) pm, α = 98.343(6)°, β = 100.747(7)°, γ = 107.642(5)°, R = 0.0289. It is worth noting that a ferrodistortive Jahn‐Teller order is observed with [MnO3F2(H2O)] octahedra strongly elongated along the F–Mn–OH2 axes perpendicular to the chain plane. The structure is stabilized by very strong hydrogen bonds. 相似文献
7.
Structure and Magnetism of Fluorides Cs2MCu3F10 (M = Mg, Mn, Co, Ni), Variants of the CsCu2F5 Type X‐ray structure determinations of single crystals showed that compounds Cs2MCu3F10 crystallize with Z = 2 in space group P21/n (No.14) (M = Mn) of the CsCu2F5 type resp. in its supergroup I2/m (No.12) (M = Mg, Co, Ni). Cs2MgCu3F10: a = 714.9(1), b = 736.8(1), c = 940.4(1) pm, b = 96.29(1)°, (Mg‐F: 199.2 pm); Cs2MnCu3F10: a = 725.1(1), b = 742.7(1), c = 951.0(2) pm, b = 97.28(3)°, (Mn‐F: 209.1 pm); Cs2CoCu3F10: a = 717.8(3), b = 739.1(2), c = 939.4(4) pm, b = 97.49(2)°, (Co‐F: 203.1 pm); Cs2NiCu3F10: a = 716.3(1), b = 737.7(1), c = 938.2(2) pm, b = 97.09(1)°, (Ni‐F: 201.0 pm). As determined directly for the Mg compound and generally concluded from the average distances M‐F noted, M substitution concerns mainly the octahedrally coordinated position of the CsCu2F5 structure, the distortion of which is very much reduced thereby. Within the remaining [CuF4] and [CuF5] coordinations, in contrast to CsCu2F5, one F ligand is disordered, in case of the Mn compound the pyramidally coordinated Cu atom, too. The magnetic properties are complex and point to frustration and spin glass effects. Only at the diamagnetically substituted variants with M = Mg, Zn no Néel point appears, which is reached at 27, 23, 36 and 55 K for M = Mn, Co, Ni and Cu, resp. At lower temperatures ferri‐ resp. weak ferromagnetism and hysteresis is observed. 相似文献
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10.
Ute Jacobs Ludger Schrder Werner Massa Carlos Elías Jesús Fuentes Pedro Núez Ursula Bentrup 《无机化学与普通化学杂志》1998,624(9):1471-1476
The crystal structures of three new diaqua-tetrafluoro-manganate(III) compounds with different organic N-cations have been determined: 2-picoH[MnF4(H2O)2] 1 (2-pico = 2-methyl-pyridine), space group P21/c, a = 9.439, b = 13.662, c = 7.641 Å, β = 91.31°; R = 0.059; TMEDAH2[MnF4(H2O)2]2 2 (TMEDA = N,N,N′,N′-tetramethyl ethane diamine), space group P21/c, a = 5.421, b = 15.970, c = 9.677 Å, β = 96.37°, R = 0.031, and TMBDAH2[MnF4(H2O)2]2 3 (TMBDA = N,N,N′,N′-tetramethyl-1,4-butane-diamine), space group P21/n, a = 12.631, b = 5.577, c = 12.976 Å, β = 98.10°, R = 0.040. All three compounds show 2 D H-bonding networks of [MnF4(H2O)2]– anions separated by the organic cations. However, the topology of the anionic H-bonding nets is different for each compound. The anions are strongly elongated by the Jahn-Teller effect and are arranged in a ferrodistortive way in compounds 1 and 2 , whereas in compound 3 the arrangement is described as in a herringbone-like antiferrodistortive variant. 相似文献
11.
Two special manganese complexes [Mn(II)(acac?)2(4,4′‐bipy)]n (bipy=4,4′‐bipyridine) (complex 1 ) and [Mn(III)(acac?)3]·4CO(NH2)2 (acacH=acetylacetone) (complex 2 ) were synthesized in the same strategy by solvothermal method. Single crystal X‐ray diffraction revealed the complex 1 consists of one‐dimensional infinite coordination chain, with the manganese centers bridged by 4,4′‐bipy. And free carbamides of complex 2 connect with each other through the hydrogen bonds to form a 14‐membered carbamide ring and a zig‐zag plane. Both enantiomers of Mn(III)(acac?)3 exist in the structure, forming a racemate. Furthermore, these enantiomers and those zig‐zag planes are linked with hydrogen bonds to form an unique spatial network. 相似文献
12.
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
13.
Georg Steinhauser Dr. Konstantin Karaghiosoff Thomas M. Klapötke Prof. Dr. 《无机化学与普通化学杂志》2008,634(5):892-894
The reaction of methylammonium nitrate and copper(II) nitrate pentahemihydrate in concentrated nitric acid yields the novel bis(monomethylammonium) tetranitratocuprate(II). By evaporation of the nitric acid at elevated temperatures single crystals suitable for crystal structure analysis by X‐ray diffraction were obtained. The crystal structure shows a clear Jahn‐Teller distortion in the octahedral nitratocuprate anion. 相似文献
14.
Pink-brown crystalline alkali-metal trifluoromonosulphatomanganates(III), A2[MnF3(SO4)] (A = NH4, Li, Na or K), have been synthesised in high yields by reacting KMnO4 or MnO(OH) with 40% HF and A2SO4 or by the reaction of MnO(OH) with 40% HF and A2S2O8 (A = NH4 or K). The chemicallly estimated oxidation state of manganese occurs between 2.9 and 3.1, and the room temperature magnetic moments lie in the range 4.0–4.2 BM. (NH4)2[MnF3(SO4)] on being pyrolysed at 340°C yields MnSO4. 相似文献
15.
Carlos Elías Jesús Fuentes Pedro Núez Vicente Daniel Rodríguez Ute Jacobs Werner Massa 《无机化学与普通化学杂志》1998,624(12):2001-2006
The synthesis and crystal structure of a new fluoromanganate(III), [(H3N(CH2)2)2NH2]2[MnF5(H2O)]3, is reported. The unit cell is unusually large: monoclinic, P21/c (no. 14), a = 41.0512(13) Å; b = 9.6469(4) Å; c = 12.8021(7) Å; β = 91.927(4)°; Z = 8, R = 0.0627 and wR2 = 0.1347. The [MnF5(H2O)]2– anions are octahedral with a strong distortion along the F–Mn OH2 axes due to the Jahn-Teller effect. A very rich intermolecular hydrogen bond framework is present, leading to chains of octahedra linked by double-hydrogen bonds. The polarized optical spectra on single crystals are explained in terms of the intraconfigurational d4 transitions split by a ligand field of C4v symmetry. 相似文献
16.
Synthesis and Crystal Structure of Manganese(II) and Zinc Amides, Mn(NH2)2 and Zn(NH2)2 Metal powders of manganese resp. zinc react with supercritical ammonia in autoclaves in the presence of a mineralizer Na2Mn(NH2)4 resp. Na2Zn(NH2)4_.0.5NH3 to well crystallized ruby‐red Mn(NH2)2 (p(NH3) = 100 bar, T = 130°C, 10 d) resp. colourless Zn(NH2)2 (p(NH3) = 3.8 kbar, T = 250°C, 60 d). The structures including all H‐positions were solved by x‐ray single crystal data: Mn(NH2)2: I41/acd, Z = 32, a = 10.185(6) Å, c = 20.349(7) Å, N(Fo) with F > 3σ (F) = 313, N(parameter) = 45, R/Rw = 0.038/0.043. Zn(NH2)2: I41/acd, Z = 32, a = 9.973(3) Å, c = 19.644(5) Å, N(Fo) with F > 3σ (F) = 489, N(parameter) = 45, R/Rw = 0.038/0.043. Both compounds crystallize isotypic with Mg(NH2)2 [1] resp. Be(NH2)2 [2]. Nitrogen of the amide ions is distorted cubic close packed. One quarter of tetrahedral voids is occupied by Mn2+‐ resp. Zn2+‐ions in such an ordered way that units M4(NH2)6(NH2)4/2 occur. The H‐atoms of the anions have such an orientation that the distance to neighboured cations is optimum. 相似文献
17.
Crystal Structure Determinations of Cs2NaCr(CN)6 and further Compounds A2BM(CN)6 (A = Rb, Cs; B = Na, K, Rb, NH4; M = Cr, Mn, Fe, Co): Tilting of Octahedra and Tolerance Factor of Cyano Cryolites The crystal structures of Cs2NaCr(CN)6 (space group P21/n, Z = 2; a = 763.2(1), b = 789.8(1), c = 1102.4(1) pm, β = 90.09(1)°) and of 9 isostructural cyano cryolites A2BM(CN)6 of the elements M = Cr, Mn, Fe, Co were determined by X‐rays at single crystals. The results, including data from the literature, were studied with respect to the interdependence of radii resp. bond lengths and cyano bridge angles M–CN–B resp. tilting of [M(CN)6] and [BN6] octahedra: The average tilt angles κ of the latter are within the range 13° ≤ κ ≤ 23° and increase linearly if the modified tolerance factor t (of range 0,87 ≥ t ≥ 0,78) decreases. 相似文献
18.
The Antimonide Triantimonidometallates(III) Cs6K3Sb[AlSb3] and Cs6K3Sb[GaSb3] The novel compounds Cs6K3Sb[AlSb3] and Cs6K3Sb[GaSb3] are formed from stoichiometric mixtures of Cs, AlSb (GaSb) and KSb in sealed niobium ampoules at 950 K. The hexagonal structures are especially characterized by one-dimensional rod packings 1∞[Cs6K3Sb] which are formed from columns of condensed (Cs6K6/2) icosahedra. The icosahedra are centered by Sb3-? anions. The trigonal planar anions [AlSb3]6-? and [GaSb3]6-? are embedded between the icosahedra columns, and they are coordinated by alkali metal atoms. The FIR spectra were assigned to the vibrations of the [MSb3]6-? anions, with respect to the 6 m2-D3h symmetry. (P63/mmc, No. 194; a = 1101.7 and 1097.2 pm; c = 1158.9 and 1150.1 pm; Z = 2; Single crystal data: 574 and 546 reflections; R = 0.073 and 0.029. Distances:d(Al? Sb) = 265.4 pm; d(Ga? Sb) = 265.1 pm; d(Sb? Cs) = 401.6–423.0 pm; d(Sb? K) = 358.6–367.3 pm). 相似文献
19.
Preparation, Raman Spectra, and Crystal Structures of V2O3(SO4)2, K[VO(SO4)2], and NH4[VO(SO4)2] The oxo-sulfato-vanadates(V) V2O3(SO4)2, K[VO(SO4)2], and NH4[VO(SO4)2] have been prepared as crystals suitable for X-ray structure determination. In all structures sulfate acts as an unidentate ligand only toward a single vanadium atom. The structure of V2O3(SO4)2 consists of a threedimensional network of pairs of cornershared VO6 octahedra with one terminal oxygen atom each, and SO4 tetrahedra. All oxygen atoms of the sulfate ions are coordinated. NH4[VO(SO4)2] and K[VO(SO4)2] are isostructural. VO6 octahedra with one terminal oxygen atom and pairs of sulfate tetrahedra form infinite chains by corner sharing. The chains are weakly interlinked to layers. The sulfate ions are distorted towards planar SO3 molecules and single oxygen atoms attached to vanadium. This structural detail gives an explanation for the mechanism of the reversible reaction K[VO(SO4)2] ? K[VO2(SO4)] + SO3 at 400°C. Raman spectra of the compounds have been recorded and interpreted with respect to their structures. Crystal data: V2O3(SO4)2, monoclinic, space group P21/a, a = 947.2(4), b = 891.3(3), c? 989.1(4) pm, β = 104.56(3)°, Z = 4, 878 unique data, R(Rw) = 0.039(0,033); K[VO(SO4)2], orthorhombic, space group P212121, a = 495.3(2), b = 869.6(9), c = 1 627(1)pm, Z = 4, 642 unique data, R(Rw) = 0,11(0,10); NH4[VO(SO4)2], orthorhombic, space group P212121, a = 495.3(1), b = 870.0(2), c = 1 676.7(4)pm, Z = 4, 768 unique data, R(Rw) = 0.088(0.083). 相似文献