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1.
Summary The crystal and molecular structures of [Mn(phen)-(OH2)Cl3] (1) and [Mn(acac)2(OH2)2]ClO4·2H2O (2) were determined. A comparison is made of the Jahn-Teller distortion in these compounds with those observed in other manganese(III) complexes with monodentate axial ligands.  相似文献   

2.
Lithium manganese oxide crystals with composition (Li0.91Mn0.09)Mn2O4 were synthesized by a flux method. The crystals have a structure closely related to that of the cubic spinel LiMn2O4, but 9% of the lithium ions in the tetrahedral 4a site are substituted by Mn2+ ions. This substitution lowers the average Mn oxidation state below 3.5+, resulting in a Jahn–Teller distortion of the MnO6 octahedron.  相似文献   

3.
Magnetic measurements onHeusler alloys (Co, Ni)2 XY are performed. The transitions from ferromagnetic to paramagnetic behaviour in some systems are of special interest.

Mit 4 Abbildungen  相似文献   

4.
Herein we report on our systematic investigations on the solution processed synthesis and characterization of transition metal halides (guanidinium, formamidinium, and methylammonium nickel bromides and chlorides as well as methylammonium manganese bromide) with the composition ABX3 (A = organic cation; B = Mn, Ni; X = Cl, Br). The investigations were carried out with respect to possible applications of 3d transition metal compounds for the perovskite solar cell. All the compounds represent different variants of the hexagonal perovskite structure (2H). Crystal structures and symmetry relations are discussed. Additionally, (CH3NH3)2MnI4, which consists of tetrahedral coordinated Mn2+, and the water containing compounds (CH3NH3)MnBr3 · 2H2O, which forms chains of edge sharing octahedra, as well as (CH3NH3)NiCl3 · 2H2O, which consists of dimers of octahedra, are presented. Investigations on the crystal structures are supported by vibrational and optical spectroscopy.  相似文献   

5.
The title compound, Cu0.5Mn2.5(PO4)2, is a copper–manganese phosphate solid solution with the graftonite‐type structure, viz. (Mn,Fe,Ca,Mg)3(PO4)2. The structure has three distinct metal cation sites, two of which are occupied by MnII and one of which accommodates CuII. Incorporation of CuII into the structure distorts the coordination geometry of the metal cation site from five‐coordinate square‐pyramidal towards four‐coordinate flattened tetrahedral, and serves to contract the structure principally along the c axis.  相似文献   

6.
A manganese(II) coordination polymer [Mn(TMB)2?·?H2O] n (1) (HTMB?=?3,4,5-trimethoxybenzoic acid) has been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, elemental analysis, powder X-ray diffraction analysis, spectroscopic (IR, solid state UV-Vis), and thermal methods. The crystal belongs to orthorhombic system, space group P212121, with cell parameters a?=?7.3001(8), b?=?11.4146(13), c?=?27.053(3)?Å, α?=?β?=?γ?=?90°, V?=?2254.3(4)?Å3, Z?=?4. In 1, TMB in two different coordination modes bridges six-coordinate manganese(II) centers forming a 1-D infinite chain coordination framework. The spectral and thermal properties of the complexes have also been studied.  相似文献   

7.
The synthesis and characterization of a binuclear carboxylated bridged manganese complex containing the heptadentate ligand N,N′-bis(2-hydroxybenzyl)-N,N′-bis(2-methylpyridyl)-2-ol-1,3-propanediamine (H3bbppnol) is reported. This complex was characterized by elemental analysis; infrared, electronic (UV–vis) and EPR spectroscopy; and conductivity measurements. The complex was immobilized on silica by either adsorption or entrapment via a sol–gel route. The obtained solids were characterized by thermogravimetric analyses (TG and DSC), UV–vis and infrared spectroscopy, and X-ray diffraction. The catalytic performance of the binuclear manganese complex in epoxidation reactions was evaluated for both homogeneous and heterogeneous systems. The catalytic investigation revealed that the complex performs well as an epoxidation catalyst for the substrates cyclohexene (26–39%) and cyclooctene (29–74%). The solids containing the immobilized complex can be recovered from the reaction medium and reused, maintaining good catalytic activity.  相似文献   

8.
The single crystal of sodium manganese arsenate (1.72/3.28/12), Na1.72Mn3.28(AsO4)3, used for analysis was prepared by solid‐state reaction at 1073 K. The compound crystallizes in the monoclinic system in space group C2/c. The structure consists of a complex network of edge‐sharing MnO6 octahedral chains, linked together by AsO4 tetrahedra, forming two distinct channels, one containing Na+ cations and the other occupied statistically by Mn+ and Na+ cations.  相似文献   

9.
Zusammenfassung Die Bromokomplexe von Mn(II) und V(III) inAN, PDC undTMP wurden auf spektrophotometrischem, potentiometrischem und konduktometrischem Wege untersucht. Folgende Koordinationsformen dürften vorliegen: [MnBr]+ (inAN), MnBr2 (tetraedrisch inAN), [MnBr3] (tetraedrisch inAN), [MnBr4]2– (tetraedrisch inAN undPDC); [VBr]2+ (oktaedrisch inTMP), [VBr2]+ (oktaedrisch inAN), VBr3 (oktaedrisch inAN), [VBr4] (oktaedrisch inAN undPDC).
Bromocomplexes of Mn(II) and V(III) were investigated inAN, PDC andTMP by spectrophotometric, potentiometric and conductometric methods. The presence of the following species is indicated: [MnBr]+ (inAN), MnBr2 (tetrahedral inAN), MnBr3] (tetrahedral inAN), [MnBr4]2– (tetrahedral inAN) andPDC); [VBr]2+ (octahedral inTMP), [VBr2]+ (octahedral inAN), VBr3 (octahedral inAN), [VBr4] (octahedral inAN andPDC).


Mit 5 Abbildungen  相似文献   

10.
Na10(Na,Mn)7Mn43(PO4)36 (sodium manganese phosphate) was synthesized hydrothermally at 873 K and 0.35 GPa. The complex crystal structure is almost identical to that of natural fillowite‐type phosphates and can be described as a hexagonal packing of three types of rods parallel to the c axis. The rods are constituted by an alternation of five‐ to seven‐coordinated Mn sites [average Mn—O = 2.243 (3) Å], of six‐ to nine‐coordinated Na sites [average Na—O = 2.590 (3) Å], of PO4 tetrahedra [average P—O = 1.548 (3) Å] and of cation vacancies.  相似文献   

11.
A new mononuclear complex Mn(bbbi)2(H2O)4(ClO4)2·(bbbi)2·(H2O)2 1 (bbbi = 1,4-bis(benzimidazol-1-yl)-2-butene) is synthesized under hydrothermal conditions and characterized by IR spectroscopy, elemental analysis, and single crystal X-ray structural analysis. Crystal data for 1: triclinic, , a = 8.8478(7) ?, b = 15.0550(11) ?, c = 16.4310(12) ?, α = 108.657(7)°, β = 104.044(7)°, Γ = 99.317(7)°, V = 1942.2(3) ?3, Z = 1, final R = 0.0621. Each manganese atom is octahedrally coordinated by four aqua ligands and two nitrogen atoms of two distinct bbbi ligands. The molecule is stabilized by hydrogen bonding and π…π interactions.  相似文献   

12.
Zusammenfassung In den beiden untersuchten Doppelfluorid-Serien, BaMF4 und Pb2 MF6 (M=Mn, Fe, Co, Ni, Cu, Zn), zeigen die Verbindungen des Cu und des Zn ein anderes Verhalten als die übrigen. Die Zn-Verbindungen sind diamagnetisch, die Cu-Verbindungen paramagnetisch. Pb2CuF6 befolgt dasCuriesche Gesetz, während BaCuF4 eineCurie-Weiss-Abweichung unterhalb 212 K aufweist.Im untersuchten Temperaturbereich zeigt sich für alle anderen Verbindungen, mit Ausnahme von Pb2FeF6, Antiferromagnetismus.
Magnetic properties of the compounds BaMF4 and Pb2 MF6 (M=Mn, Fe, Co, Ni, Cu, Zn)
Two series of double fluorides, BaMF4 and Pb2 MF6 (M=Mn, Fe, Co, Ni, Cu, Zn) have been studied, the compounds of Cu and Zn differing in behaviour from the others. The Zn componds are diamagnetic, the Cu compounds paramagnetic. Pb2CuF6 conforms toCurie's law while BaCuF4 exhibits aCurie-Weiss deviation below 212° K.With the exception of Pb2FeF6, all the other compounds show antiferromagnetism in the studied temperature range.


Mit 5 Abbildungen

Herrn Prof. Dr.Hans Nowotny ergebenst gewidmet.  相似文献   

13.
New five-coordinate complexes Co(ISQ-Pri)2Cl, Co(ISQ-Me)2Cl, Co(ISQ-Me)2I, Co(ISQ-Me)2(SCN), Mn(ISQ-Pri)2Cl, and Fe(ISQ-Me)2Br (ISQ-Pri and ISQ-Me are the 4,6-di-tert-butyl-N-(2,6-diisopropylphenyl)-and 4,6-di-tert-butyl-N-(2,6-dimethylphenyl)-o-iminobenzosemiquinone radical anions, respectively) were synthesized. The complexes were characterized by UV-Vis and IR spectroscopy and magnetochemistry. The molecular structures of the Fe(ISQ-Me)2Br and Mn(ISQ-Pri)2Cl complexes were established by X-ray diffraction. The singlet ground state (S = 0) of the cobalt complexes is caused by antiferromagnetic coupling between the unpaired electrons of the radical ligands (S = 1/2) through the fully occupied atomic orbitals of low-spin cobalt(III) (d6, S = 0). The effective magnetic moments of the complexes at 10 K are 0.18 μB for Co(ISQ-Pri)2Cl and 0.16 μB for Co(ISQ-Me)2I. The ground state of the manganese complex is triplet (S = 1). Two unpaired electrons of the o-iminobenzosemiquinone ligands are strongly antiferromagnetically coupled with two of four unpaired electrons of high-spin manganese(III) (d4, S = 2). Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 43–51, January, 2006.  相似文献   

14.
The crystal structure of a new form of dehydrated manganese(II) acetate, poly[[hexa‐μ3‐acetato‐trimanganese(II)] acetonitrile solvate], {[Mn3(CH3COO)6]·CH3CN}n, (I), reveals a three‐dimensional polymeric structure based on an {Mn3} trimer. The {Mn3} asymmetric unit contains three crystallographically independent Mn positions, comprising a seven‐coordinate center sharing a mirror plane with a six‐coordinate center, and another six‐coordinate atom located on an inversion center. Two of the four crystallographically independent acetate (OAc) ligands, as well as the acetonitrile solvent molecule, are also located on the mirror plane. The Mn atoms are connected by a mixture of Mn—O—Mn and Mn—OCO—Mn bridging modes, giving rise to face‐ and corner‐sharing interactions between manganese polyhedra within the trimers, and edge‐ and corner‐sharing connections between the trimers. The network contains substantial pores which are tightly filled by crystallographically located acetonitrile molecules. This structure represents the first porous structurally characterized phase of anhydrous manganese(II) acetate and as such it is compared with the closely related densely packed anhydrous manganese(II) acetate phase, solvent‐free β‐Mn(OAc)2.  相似文献   

15.
Synthesis and Crystal Structure of K2Mn3S4 Single crystals of K2Mn3S4 have been prepared by a fusion reaction of potassium carbonate with manganese in a stream of hydrogen sulfide at 900 °C. K2Mn3S4 crystallizes in a new monoclinic layered structure type (P2/c, a = 7.244(2) Å, b = 5.822(1) Å, c = 11.018(5) Å, β = 112.33(3)°, Z = 2) which can be described as a stacking variant of the orthorhombic Cs2Mn3S4 structure type. Measurements of the magnetic susceptibilities show antiferro‐magnetic interactions.  相似文献   

16.
The reaction of [RhCl2(HPhL)(PhL)] with MII(ClO4)2·6H2O in presence of alkali has furnished trinuclear [RhCl2(PhL)2]2M(H2O)2·H2O (HPhL is phenylazobenzaldoxime; M = Mn, Co, Ni). A similar reaction with MI(PPh3)2NO3 yielded binuclear [RhCl2(PhL)2]M(PPh3)2 (M = Cu, Ag). In these molecules the oximato group acts as a bridge between RhIII (bonded at N) and MII or MI (bonded at O). In structurally characterized [RhIIICl2(PhL)2]2Mn(H2O)2.H2O the centrosymmetric distorted octahedral MnO6 coordination sphere is spanned by four oximato oxygen atoms and two water molecules lying in trans position. In the lattice the neighbouring molecules are held together by H2O⋯H2O⋯H2O hydrogen bonds generating infinite zigzag chains. The manganese atoms lie parallel to the C-axis, the shortest Mn...Mn distance being 7.992 ?. Magnetic exchange interactions if any are small as seen in room temperature magnetic moments. The manganese system displays a strong EPR signal near g = 2.00. In the complex [RhCl2(PhL)2]Cu(PPh3)2 the copper atom is coordinated to two oximato oxygen atoms and the two phosphorus atoms in a distorted tetrahedral geometry. The softness of the phosphine ligand is believed to sustain the stable coordination of hard oximato oxygen to soft CuI. The coordination sphere of the RhIII atom in both the complexes is uniformly trans-RhN4Cl2.  相似文献   

17.
A new complex [Mn(hfac)2NIT(Ph-m-OPh)] has been synthesized and structurally characterized by X-ray diffraction. It crystallizes in the monoclinic space group P2(1)/c. The structure consists of a 1-D chain with Mn(II) bridged by NIT(Ph-m-OPh). The manganese(II) is in a distorted octahedral environment formed by one oxygen from NIT(Ph-m-OPh) and three atoms from hexafluoro acetylacetone (hfac) in the equatorial plane and two oxygens from hfac and the other NIT(Ph-m-OPh) in the axial position. The units of [Mn(hfac)2NIT(Ph-m-OPh)] are connected as a 1-D chain by Mn(II) and oxygen of N–O in bridging NIT(Ph-m-OPh) along the b-axis. The 2-D layer in the ab plane is formed via hydrogen interactions to connect neighboring chains. The complex exhibits intramolecular antiferromagnetic interactions between Mn(II) and NIT(Ph-m-OPh).  相似文献   

18.
Contributions on the Bonding Behaviour of Oxygen in Inorganic Solids. III [1] Mn2P2O7, Mn2P4O12 und Mn2Si(P2O7)2 — Crystal Growth, Structure Refinements and Electronic Spectra of Manganese(II) Phosphates By chemical vapour transport reactions in a temperature gradient single crystals of Mn2P2O7 (1050 → 950 °C) and Mn2P4O12 (850 → 750 °C) have been obtained using P/I mixtures as transport agent. Mn2Si(P2O7)2 was crystallized by isothermal heating (850 °C, 8d; NH4Cl as mineralizer) of Mn2P4O12 und SiO2. In Mn2Si(P2O7)2 [C 2/c, a = 17.072(1)Å, b = 5.0450(4)Å, c = 12.3880(9)Å, β = 103.55(9)°, 1052 independent reflections, 97 variables, R1 = 0.023, wR2 = 0.061] the Mn2+ ions show compressed octahedral coordination (d¯Mn—O = 2.19Å). The mean distance d¯Mn—O = 2.18Å was found for the radially distorted octahedra [MnO6] in Mn2P4O12 [C 2/c, Z = 4, a = 12.065(1)Å, b = 8.468(1)Å, c = 10.170(1)Å, β = 119.29(1)°, 2811 independent reflections, 85 variables, R1 = 0.025, wR2 = 0.072]. Powder reflectance spectra of the three pink coloured manganese(II) phosphates have been measured. The spectra show clearly the influence of the low‐symmetry ligand fields around Mn2+. Observed d—d electronic transition energies and the results of calculations within the framework of the angular overlap model (AOM) are in good agreement. Bonding parameters for the manganese‐oxygen interaction in [Mn2+O6] chromophors as obtained from the AOM treatment (B, C, Trees correction α, eσ, eπ) are discussed.  相似文献   

19.
Abstract

A mixed ligand 1:2 manganese(II) azido complex of ethyl nicotinate has been synthesized and characterized by spectroscopic and crystallographic methods. The structure consists of a two-dimensional manganese-azido compound with each manganese atom in a trans octahedral environment, bonded to four azido ligands [Mn?N = from 2.199(4) Å to 2.231(3) Å] and two axial ethyl nicotinate ligands [Mn-N = 2.285(3) and 2.308(3) Å]. Two azido ligands are coordinated end-on between the manganese atoms giving planar and centrosymmetric Mn2N2 units. Each Mn2N2 unit is linked to four neighboring Mn2N2 units by means of four end-to-end azido bridges. The IR and Raman spectra correlate with the structure of the complex. The vibrational bands are compared with those of the free ligand. The EPR spectra of polycrystalline powder and solutions of the complex are measured at room temperature and discussed. The thermal decomposition of the complex was investigated derivatographically under nitrogen.  相似文献   

20.
Phosphoraneiminato Complexes of Manganese(II) and Nickel(II) with Heterocubane Structure. Crystal Structures of [MCl(NPEt3)]4 with M = Mn and Ni The phosphoraneiminato complexes [MCl(NPEt3)]4 with M = manganese and nickel as well as [MnBr(NPEt3)]4 are formed from the anhydrous halides MX2 and excess phosphoraneimine Me3SiNPEt3 by fusion reaction. They form paramagnetic, moisture-sensitive, orange (M = Mn) and turquoisegreen (M = Ni) crystals, respectively, which are characterized by i.r. spectroscopy and by crystal structure determinations. [MnCl(NPEt3)]4 ( 1 ): Space group C2/c, Z = 4, structure solution with 3 591 unique reflections, (2 811 > 2σ(I)) R = 0.036. Lattice dimensions at -50°C: a = 2104.3, b = 1100.6, c = 1966.5 pm, β = 115.87°. [NiCl(NPEt3)]4 ( 2 ): Space group C2/c, Z = 4, structure solution with 2 711 unique reflections, (1611 > 2σ(I)) R = 0.056. Lattice dimensions at ?50°C: a = 2051.6, b = 1099.2, c = 1954.6 pm, β = 115.80°. 1 and 2 are isostructural with one another. They form heterocubane structures in which the metal atoms are linked via μ3-N-bridges of the phosphoraneiminato groups with M4N4 bridge-type bond angles close to 90°.  相似文献   

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