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The title compound, [Fe(C3H7NO)6][Cd2Cl7], crystallizes in the trigonal space group R3̅ and is assembled from discrete [Fe(DMF)6] 3+ cations (DMF = N,Ndimethylformamide) and [Cd2Cl7] 3- anions. In the cation, the iron(III) atom, located on a special position of 3̅ site symmetry, is coordinated by six oxygen atoms from DMF ligands with all Fe—O distances being equal [2.0072 (16) A˚ ]. A slight distortion of the octahedral environment of the metal comes from the cis O—Fe—O angles deviating from the ideal value of 90 [86.85 (7) and 93.16 (7)] whilst all the trans angles are strictly 180. The central Cl atom of the [Cd2Cl7] 3- anion is also located on a special position of 3̅ site symmetry and bridges two corner sharing, tetrahedrally coordinated CdII atoms. The two Cd atoms and the central Cl atom are colinear. The two sets of terminal chloride ligands on either side of the dumbbell-like anion are rotated relative to each other by 30. In the crystal, the cations and anions, stacked one above the other along the c-axis direction, are held in place principally by electrostatic interactions. There are also C—H...Cl and C—H...O interactions, but these are rather weak. Of the six crystal structures reported to date for ionic salts of [Fe(DMF)6] n+ cations (n = 2, 3), five contain FeII ions. The title compound is the second example of a stable compound containing the [Fe(DMF)6] 3+ cation. The existence of both [Fe(DMF)6] 2+ and [Fe(DMF)6] 3+ cations shows that the DMF ligand coordination sphere can accommodate changes in the charge and spin states of the metal centre. [ABSTRACT FROM AUTHOR]

A new organic-inorganic hybrid salt [L]2[MnCl4] (I) where L+ is the 2-methyl-3-(pyridin-2-yl)imidazo[1,5-a]pyridinium cation, is built of discrete organic cations and tetrachloridomanganate(II) anions. The L+ cation was formed in situ in the oxidative cyclocondensation of 2-pyridinecarbaldehyde and CH3NH2·HCl in methanol. The structure was refined as a two-component twin using PLATON (Spek, 2020[Spek, A. L. (2020). Acta Cryst. E76, 1-11.]) to de-twin the data. The twin law (-1 0 0 0 - 1 0 0.5 0 1) was applied in the refinement where the twin component fraction refined to 0.155-(1). The compound crystallizes in the space group P21/c with two crystallographically non-equivalent cations in the asymmetric unit, which possess similar structural conformations. The fused pyridinium and imidazolium rings of the cations are virtually coplanar [dihedral angles are 0.89-(18) and 0.78-(17)°]; the pendant pyridyl rings are twisted by 36.83-(14) and 36.14-(13)° with respect to the planes of the remaining atoms of the cations. The tetrahedral MnCl42- anion is slightly distorted with the Mn-Cl distances falling in the range 2.3469-(10)-2.3941-(9)-Å. The distortion value of 0.044 relative to the ideal tetrahedron was obtained by continuous shape measurement (CShM) analysis. In the crystal, the cations and anions form separate stacks propagating along the a-axis direction. The organic cations display weak π-π stacking. The anions, which are stacked identically one above the other, demonstrate loose packing; the minimum Mn...Mn separation in the cation stack is approximately 7.49-Å. The investigation of the fluorescent properties of a powdered sample of (I) showed no emission. X-band EPR data for (I) at 293 and 77-K revealed broad fine structure signals, indicating moderate zero-field splitting. [ABSTRACT FROM AUTHOR]

The new heterometallic complex, aqua-1κO-bis(μ2-2-iminomethyl-6-methoxyphenolato-1κ2O1,O6:2κ2O1,N)bis(thiocyanato-1κN)calcium(II)copper(II), [CaCu(C8H8NO2)2(NCS)2(H2O)], has been synthesized using a one-pot reaction of copper powder, calcium oxide, o-vanillin and ammonium thiocyanate in methanol under ambient conditions. The Schiff base ligand (C8H9NO2) is generated in situ from the condensation of o-vanillin and ammonia, which is released from the initial NH4SCN. The title compound consists of a discrete binuclear molecule with a {Cu(μ-O)2Ca} core, in which the Cu···Ca distance is 3.4275-(6)-Å. The coordination geometries of the four-coordinate copper atom in the [CuN2O2] chromophore and the seven-coordinate calcium atom in the [CaO5N2] chromophore can be described as distorted square planar and pentagonal bipyramidal, respectively. In the crystal, O-H···S hydrogen bonds between the coordinating water molecules and thiocyanate groups form a supramolecular chain with a zigzag-shaped calcium skeleton. [ABSTRACT FROM AUTHOR]

A tetranuclear heterometallic complex formulated as [Co2Cu2(L)3(ea)(H2O)(NCS)2], where H2L = 2-((2-hydroxyethyl)iminomethyl)-phenol and Hea = 2-aminoethanol, has been obtained by self-assembly and characterized by single crystal X-ray diffraction. The crystal structure of the complex represents a new {CoIICoIIIM2} type of cobalt-based oxide cubane complex according to the classification which has been made via CSD structural analysis. [ABSTRACT FROM AUTHOR]

The “direct synthesis” approach, namely one-pot reaction of metal powders and ammonium salt with a methanol solution of a polydentate Schiff base (H2L) formed in situ from salicylaldehyde and ethanolamine, has been successfully used for the preparation of the new heterometallic compounds [Cu3Mn(L)4(CH3OH)3]I3 (1), [Cu3Mn(L)4(CH3OH)3(H2O)]NCS·H2O (2), [Cu3Mn(L)4(CH3OH)(H2O)2.55]Br·0.45H2O (3) and [Cu3Mn(L)4(H2O)3.4]BF4·0.6H2O (4). Crystallographic analysis revealed that 1–4 are based on the tetranuclear core {CuII3MnIII(μ3-O)4} where the metal centres are joined by the oxygen bridges of Schiff base ligands forming a cube-like arrangement. The novel heterometallic compound [Cu3Mn(L)4(CH3OH)3]2[Mn(NCS)4]·2CH3OH (5) has been obtained by the “building block” approach using the reaction of [Cu(HL)2] with manganese acetate and NH4NCS in methanol. The crystal structure of 5 revealed the {CuII3MnIII(μ-O)2(μ3-O)2} metal core which can be viewed as a double open cube. In spite of a similar {Cu3MnO4} atom set in the cores of 1–5, the complexes show rather different molecular structures and significantly differ by the number and combinations of coordinated CH3OH/H2O solvent molecules. Variable-temperature (2–300 K) magnetic susceptibility along with variable-field magnetization measurements of 1–5 showed a decrease of the effective magnetic moment value at low temperature, indicative of the antiferromagnetic coupling of medium size (−55 to −22 cm−1). For these systems resembling a compressed prism the coupling constant in walls J4 correlates with the averaged bonding angles in walls α: J4vs. α develops approximately according to a straight line. [ABSTRACT FROM AUTHOR]

Four new heterobimetallic complexes [CuL 1 ][MnCl 4 ] ( 1 ), [CuL 2 ][MnCl 4 ] ( 2 ), [NiL 1 ][MnCl 4 ] ( 3 ), [NiL 2 ][MnCl 4 ] ( 4 ) (L 1 = 4,6,6-trimethyl-1,9-diamino-3,7-di-aza-nona-3-ene; L 2 = 1,15-dihydroxy-7,9,9-trimethyl-3,6,10,13-tetra-aza-pentadeca-6-ene) have been prepared from elemental metals, ethylenediamine dihydrochloride or its N-(2-hydroxyethyl) derivative and acetone by the template condensation reaction. All complexes have been characterized by elemental analysis, IR and UV-Visible spectroscopy. The structures of 2 and 3 have been determined by X-ray crystallography ( 2 : Orthorhombic, Pna2 1, a = 20.136(4), b = 11.185(2), c = 10.251(2)Å, Z = 4; 3 : Orthorhombic, Pca2 1, a = 14.335(2), b = 11.405(2), c = 11.154(2)Å, Z = 4 ). Both crystals consist of alternating complex cations [ML] 2+ and anions [MnCl 4 ] 2- linked together by N-H···Cl-Mn and O-H···Cl-Mn hydrogen bonds forming 2D corrugated sheets in ( 2 ) and 1D helical chains in ( 3 ). Complex 2 represents the first single crystal structure elucidation of the complex containing L 2 . [ABSTRACT FROM AUTHOR]