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1.
A tetranuclear manganese complex [Mn4(HL)4(MeOH)4(SCN)2]·3MeOH (1) and a one-dimensional assembly of [Mn4] units, [Mn4(HL)4(MeOH)4(N(CN)2)2]·2.5MeOH (2) (H3L = 2,6-bis(hydroxymethyl)-4-methylphenol), have been synthesized and studied. Complexes 1 and 2 crystallize in the triclinic space group P $ \bar 1 $ \bar 1 and monoclinic space group P21/n, respectively. Complex 1 possesses a mixed-valence tetranuclear dicubane unit, which comprises two MnII and two MnIII ions. Complex 2 is built from the similar tetranuclear [Mn4] units connected through two N(CN)2 anions into a 1-D chain. The temperature dependence of the magnetic susceptibilities of 1 and 2 indicates ferromagnetic interactions between the manganese ions. Frequency-dependent out-of-phase signals of alternating current magnetic susceptibilities are observed in the low temperature range for both complexes, indicating a slow magnetic relaxation.  相似文献   

2.
Three cyanide-bridged dodecanuclear macrocyclic wheel-like complexes [Cr(bpmb)(CN)2]6[Mn(5-Brsalpn)]6·12H2O (1), [Co(bpmb)(CN)2]6[Mn(5-Brsalpn)]6·12H2O (2) and [Co(bpmb)(CN)2]6[Mn(5-Clsalpn)]6·24H2O·8CH3CN (3) [bpmb2−= 1,2-bis(pyridine-2-carboxamido)-4-methylbenzenate dianion; 5-Brsalpn2− = N,N′-propylenebis(5-bromosalicylideneaminato) dianion; 5-Clsalpn2− = N,N′-propylenebis(5-chlorosalicylideneaminato) dianion] have been synthesized and their crystal structures and magnetic properties have been investigated. The three compounds are structurally isomorphous and consist of alternating Mn(III)-Schiff base cations and [M(bpmb)(CN)2] anions, generating cyanide-bridged nanosized dodecanuclear macrocyclic structures with an approximate diameter of 2 nm. The study of the magnetic properties of complex 1 reveals an antiferromagnetic interaction between the Cr(III) and Mn(III) ions through the cyanide bridges. A best-fit to the magnetic susceptibility of the complex leads to a magnetic coupling constant of J CrMn = −2.65(6) cm−1 on the basis of a one-dimensional alternating chain model with the Hamiltonian $ H = - J_{CrMn} \sum\limits_{i = 0}^N {S_i \cdot S_{i + 1} } $ H = - J_{CrMn} \sum\limits_{i = 0}^N {S_i \cdot S_{i + 1} } .  相似文献   

3.
By the interaction of aqueous solutions of salts of the [Re6Se8(CN)6]4− cluster anion with salts of Nd(III), Tb(III), and Yb(III) lanthanides in the presence of tetraatomic alcohol erythritol (butane-1,2R,3S,4-tetraol) three new compounds are obtained: K[Nd(C4H10O4)(H2O)4{Re6Se8(CN)6}]·4H2O (P $ \bar 1 $ \bar 1 space group, a = 11.544 ?, b = 13.643 ?, c = 13.838 ?, α = 111.97°, β = 108.08°, γ = 90.08°) (1); [{Yb2(C4H9O4)2 × (H2O)2}{Re6Se8(CN)6}]·5H2O (P $ \bar 1 $ \bar 1 space group, a = 10.308 ?, b = 10.505 ?, c = 11.154 ?, α = 88.21°, β = 81.83°, γ = 78.50°) (2); [{Tb2(C4H9O4)2(C4H10O4)}{Re6Se8(CN)6}]·4H2O (P $ \bar 1 $ \bar 1 space group, a = 10.002 ?, b = 10.276 ?, c = 11.762 ?, α = 91.32°, β = 104.01°, γ = 106.02°) (3). The structures of these compounds are the coordination polymers (chain (2) and grids (1 and 3)) with different coordination modes of erythritol to the lanthanide cations.  相似文献   

4.
The sodium hydrogen oxovanadate [Na2(H2O)8] 2H2[V10O28] · 4H2O was synthesized and studied by TGA, X-ray diffraction, and NMR and IR spectroscopy. The crystals are triclinic, space group P $ \bar 1 $ \bar 1 , a = 8.545(7) ?, b = 10.827(2) ?, c = 11.627(2) ?, α = 105.48(3)°, β = 99.38(3)°, γ = 101.29(3)°, V = 989.9(3) ?3, ρ(calcd) = 2,381 g/cm3, Z= 1.  相似文献   

5.
Eight isostructural polymeric coordination compounds of the general formula [Ln(DMF)(H2O)4][Ln(DMF)2(H2O)4][M4Te4(CN)12]·DMF·nH2O (Ln = Er, Ho, Gd, or Sm; M = W or Mo) were prepared for the first time by evaporation in air of aqueous solutions containing the cuboidal telluride anionic complex of tungsten [W4Te4(CN)12]6– or molybdenum [Mo4Te4(CN)12]7–, lanthanide chlorides, and dimethylformamide. The resulting polymeric coordination complexes with layered structures were characterized by X-ray diffraction analysis and IR spectra. The magnetic susceptibilities of the gadolinium complexes were measured.  相似文献   

6.
Summary The new complex double saltscw-[Co(NH3)(en)2(H2O)]2 [M(CN)4]3 (en = ethylenediamine; M = Ni, Pd or Pt),cis-[Co(NH3(en)2(H2O)]2[FeNO(CN)5]3 andcis-[Co(NH3)(en)2(H2O)][Co(CN)6] have been synthesized and by anation in the solid state the corresponding new dinuclear complexes with a cyano bridgecis- ortrans-[(NH3)(en)2Co-NC-M(CN)3]2 [M(CN)4] (M = Ni, Pd or Pt);cis-, trans-[(NH3)(en)2Co-NC-FeNO(CN)4]2[FeNO(CN)5] andcis-[(NH3)(en)2Co-NC-Co(CN)5 have been prepared. The complexes have been characterized by chemical analysis, t.g. measurements, and by i.r. and electronic spectroscopy. With [Ni(CN)4][2– and [Co(CN)in]6 3– only thecis-isomer is produced; with [Pd(CN)4]2–, [Pt(CN)4]2– and [FeNO(CN)5]2– thetrans- isomer is the dominant species. The dinuclear complex derived from [Pt(CN)4]2– shows strong Pt-Pt interactions both in the solid state and in solution.  相似文献   

7.
Crystal Structures of Octacyanomolybdates(IV). IV Dodecahedral [Mo(CN)8] Coordination of the Cyano‐Bridged Cobalt and Nickel Ammin Complexes MII2(NH3)8[Mo(CN)8] · 1.5 H2O (MII = Co, Ni) and Ni2(NH3)9[Mo(CN)8] · 2 H2O At single crystals of the hydrated cyano complexes Co2(NH3)8[Mo(CN)8] · 1.5 H2O (a = 910.0(4), b = 1671(2), c = 1501(1) pm, β = 93.76(6)°) and Ni2(NH3)8[Mo(CN)8] · 1.5 H2O (a = 899.9(9), b = 1654.7(4), c = 1488(1) pm, β = 94.01°), isostructurally crystallizing in space group P21/c, Z = 4, and of trigonal Ni2(NH3)9[Mo(CN)8] · 2 H2O (a = 955.1(1), c = 2326.7(7) pm, P31, Z = 3), X‐ray structure determinations were performed at 168 resp. 153 K. The [Mo(CN)8]4– groups of the three compounds, prepared at about 275 K and easily decomposing, show but slightly distorted dodecahedral coordination (mean distances Mo–C: 216.3, 215.4 and 216.1 pm). Within the monoclinic complexes the anions twodimensionally form cyano bridges to the ammin cations [M(NH3)4]2+ and are connected with the resulting [MN6] octahedra (Co–N: 215.1 pm, Ni–N: 209.8 pm) into strongly puckered layers. The trigonal complex exhibits a chain structure, as one [Ni(NH3)5]2+ cation is only bound as terminal octahedron (Ni–N: 212.0 pm). Details and the influence of hydrogen bridges are discussed.  相似文献   

8.
The Crystal Structure of the Hydrated Cyano Complexes NMe4MnII[(Mn, Cr)III(CN)6] · 3 H2O and NMe4Cd[MIII(CN)6] · 3 H2O (MIII = Fe, Co): Compounds Related to Prussian Blue The crystal structures of the isotypic tetragonal compounds (space group I4, Z = 10) NMe4MnII · [(Mn, Cr)III(CN)6] · 3 H2O (a = 1653.2(4), c = 1728.8(6) pm), NMe4Cd[Fe(CN)6] · 3 H2O (a = 1642.7(1), c = 1733.1(1) pm) and NMe4Cd[Co(CN)6] · 3 H2O (a = 1632.1(2), c = 1722.4(3) pm) were determined by X‐rays. They exhibit ⊥ c cyanobridged layers of octahedra [MIII(CN)6] and [MIIN4(OH2)2], which punctually are interconnected also || c to yield altogether a spaceous framework. The MII atoms at the positions linking into the third dimension are only five‐coordinated and form square pyramids [MIIN5] with angles N–MII–N near 104° and distances of Mn–N: 1 × 214, 4 × 219 pm; Cd–N: 1 × 220 resp. 222, 4 × 226 resp. 228 pm. Further details and structural relations within the family of Prussian Blue are reported and discussed.  相似文献   

9.
The polymeric coordination compound {[Ge(μ-HCit)2Ba(H2O)3] · 3H2O} n (H4Cit = citric acid) was obtained for the first time for germanium(IV) citrates. The compound was characterized by elemental analysis, thermogravimetry, IR spectroscopy, and X-ray crystallography. Crystals of the compound are triclinic, a = 7.422(4) ?, b = 10.668(4) ?, c = 14.342(6) ?, α = 91.31(3)°, β = 95.81(4)°, γ = 104.08(4)°, V = 1094.5(8) ?3, Z = 2, space group P $ \bar 1 $ \bar 1 , R1 = 0.0479 for 2284 reflections with I > 2σ(I). Two crystallographically independent octahedral [Ge(HCit)2]2− anions are linked by Ba2+ ions to form a polymeric chain. The coordination number of Ba atoms is equal to 9. The chains are linked to each other and crystal water molecules by hydrogen bonds.  相似文献   

10.
Subsolidus phase relations in the Cs2MoO4-MMoO4-Zr(MoO4)2 (M = Mn, Zn) ternary systems were determined, and two groups of new isostructural triple molybdates were synthesized: Cs2MZr(MoO4)4 and Cs2MZr2(MoO4)6 (M = Mn, Mg, Co, Zn). Cs2MnZr2(MoO4)6 and Cs2MnZr(MoO4)4 crystals were grown by spontaneous flux crystallization and used in structure solution for both groups of compounds. The Cs2MnZr2(MoO4)6 structure (a =13.4322(2) ?, c = 12.2016(3) ?, group R3, Z = 3, R = 0.0367) is a new structure type characterized by a mixed three-dimensional framework built of corner-sharing MoO4 tetrahedra and (M, Zr)O6 octahedra where large channels are occupied by cesium cations. Cs2MnZr2(MoO4)4 (a =5.3890(1) ?, c = 8.0685(3) ?, space group P $ \bar 3 $ \bar 3 m1, Z = 0.5, R = 0.0247) has the layered glaserite-like KAl(MoO4)2 type structure, where Al3+ octahedral positions are randomly occupied by a 0.5M2+ + 0.5Zr4+ mixture.  相似文献   

11.
A new 3D coordination polymer, [LaAg(Pydc)(HPydc)(C2O4)0.5(H2O)2] n (I) (H2Pydc = pyridine-3,5-dicarboxylic acid), has been hydrothermally synthesized and characterized by elemental analyses and single crystal X-ray diffraction. The X-ray diffraction analysis reveals that I (C15H11AgLaN2O12) crystallizes in triclinic space group P $ \bar 1 $ \bar 1 and features an interesting 3D framework constructed by 2D layers via strong Ag-Ag interactions. Unit cell parameters for I (n = 1): a = 7.749(2), b = 8.316(1), c = 14.239(3) ?, α = 97.64(2)°, β = 100.12(2)°, γ = 94.37(2)°, and Z = 2.  相似文献   

12.
A bimetallic cyano-bridged complex {[Mn(ImH)(H2O)2]2[Mo(CN)8]·4H2O} n (ImH?=?imidazole) has been prepared and characterized. Single-crystal X-ray analysis reveals that the complex crystallizes in space group C2/c with a?=?15.665(2), b?=?14.616(2), c?=?12.307(2)?Å, α?=?90, β?=?108.31(1), γ?=?90°. The structure of the complex demonstrates a three-dimensional network through cyano-bridges. Each Mo(IV) atom has six –CN–Mn linkages and two terminal cyano ligands arranged in a square antiprismatic arrangement. The Mn(II) atom is in a distorted octahedral environment formed by three MoCN?→?Mn linkages along with one imidazole and two water molecules in cis configuration. Variable temperature magnetic susceptibility shows an antiferromagnetic coupling between Mn2+ ions through the NC–MoIV–CN diamagnetic bridges within the three-dimensional network. The IR spectra have also been investigated.  相似文献   

13.
In the crystals of [Ba(H2O)4][Co(Pic)2(CN)2]2 · 4.41H2O (tetragonal system, a = b = 10.9390(4) ?, c = 31.7624(15) ?, Z = 4, space group P43), the trans(O)-cis(CN)-[Co(Pic)2(CN)2] anions are incorporated into cellular infinite layers whose sites contain Ba2+ ions, which are connected to four neighboring complexes through the oxygen atoms of the carboxy groups of the 2-picolinate ions. Four O atoms of the water molecules complete the Ba coordination polyhedron to a distorted square antiprism. Original Russian Text ? M. Zabel, V.I. Pavlovskii, A.L. Poznyak, 2007, published in Zhurnal Neorganicheskoi Khimii, 2007, Vol. 52, No. 3, pp. 417–420.  相似文献   

14.
A new complex compound, bis[(18-crown-6)oxonium]tetrabromomanganese(II), 2[(H3O)+(18-crown-6)]·[MnBr4]2–, was prepared and studied by X-ray diffraction to reveal its unusual cubic crystal structure, space group Fd $ \bar 3 A new complex compound, bis[(18-crown-6)oxonium]tetrabromomanganese(II), 2[(H3O)+(18-crown-6)]·[MnBr4]2–, was prepared and studied by X-ray diffraction to reveal its unusual cubic crystal structure, space group Fd, a 20.424 ?, and Z 8. In this crystal structure, the complex cation [(H3O)+(18-crown-6)] the point symmetry position and the anion [MnBr4]2− with the point symmetry 23. The complex cation [(H3O)+(18-crown-6)] has a guest-host structure, and, unlike metal complexes by hydrogen bonds between H3O+ hydrogens and 18-crown-6 oxygens, rather than by coordination bonds. The pyramidal cation H3O+ in this crystal structure is statistically disordered, and the tetrahedral anion [MnBr4]2− is reorientationally disordered. Original Russian Text ? A.N. Chekhlov, 2008, published in Zhurnal Obshchei Khimii, 2008, vol. 78, No. 10, pp. 1622–1626.  相似文献   

15.
Conditions of the hydrothermal synthesis of scandium hydrogen orthophosphate Li2Sc[H(PO4)2] (I) have been studied and the range of its monomineral crystallization have been determined. The existence of bound hydrogen in the structure has been confirmed by IR spectroscopy. The crystals of I are monoclinic: a = 4.857(1) ?, b = 8.198(2) ?, c = 7.664(2) ?, β = 104.097(5)°, space group P21/n, Z = 2. The structure was solved by direct methods and refined by full-matrix least-squares calculation in the anisotropic approximation for all non-hydrogen atoms, R obs = 0.0215, R wall = 0.0335 (705 reflections with I > 3σ(I)). The basis of the structure is a mixed anionic para-framework {Sc[H(PO4)2]}3∞2−, composed of vertex-sharing ScO6 octahedra and PO4 tetrahedra. The structural unit of the para-framework is the microblock [ScP6O24] with symmetry $ \bar 1 $ \bar 1 . The microblocks are condensed in columns running in the [100] direction to form through channels filled with Li+ cations (CN = 5). A model with splitting of the hydrogen atom position implying the formation of a strong asymmetric nonlinear H-bond has been suggested and considered. The compound is stable to 400°C. The results of studying compound I are presented together with the data on the Fe- and In-containing Li2MIII[H(PO4)2] analogues.  相似文献   

16.
We present a comprehensive study of the structural properties and the thermal expansion behavior of 17 different Prussian Blue Analogs (PBAs) with compositions MII3[(M′)III(CN)6]2·nH2O and MII2[FeII(CN)6nH2O, where MII=Mn, Fe, Co, Ni, Cu and Zn, (M′)III=Co, Fe and n is the number of water molecules, which range from 5 to 18 for these compounds. The PBAs were synthesized via standard chemical precipitation methods, and temperature-dependent X-ray diffraction studies were performed in the temperature range between −150 °C (123 K) and room-temperature. The vast majority of the studied PBAs were found to crystallize in cubic structures of space groups Fm3?m, F4?3m and Pm3?m. The temperature dependence of the lattice parameters was taken to compute an average coefficient of linear thermal expansion in the studied temperature range. Of the 17 compounds, 9 display negative values for the average coefficient of linear thermal expansion, which can be as large as 39.7×10−6 K−1 for Co3[Co(CN)6]2·12H2O. All of the MII3[CoIII(CN)6]2·nH2O compounds show negative thermal expansion behavior, which correlates with the Irving–Williams series for metal complex stability. The thermal expansion behavior for the PBAs of the MII3[FeIII(CN)6]2·nH2O family are found to switch between positive (for M=Mn, Co, Ni) and negative (M=Cu, Zn) behavior, depending on the choice of the metal cation (M). On the other hand, all of the MII2[FeII(CN)6nH2O compounds show positive thermal expansion behavior.  相似文献   

17.
The formation conditions and physicochemical properties of binary decavanadates M4Na2V10O28 · 10H2O (M=K, Rb, NH4), synthesized by crystallization from saturated solutions of the NaVO3-MH2AsO4-H2O systems, were studied by chemical analysis, X-ray powder diffraction, microscopy, thermogravimetry, and IR spectroscopy. To optimize the synthesis conditions of M4Na2V10O28 · 10H2O, the ( 1-x)NaVO3 · 2H2O · xMH2AsO4-H2O (0.2 ≤ x ≤ 0.8) isomolar series method was applied to studying the interaction in the NaVO3-MH2AsO4-H2O systems (M = K, Rb, Cs) at the 0.4 mol/L total molar concentration of NaVO3 and MH2AsO4 in solutions. The studied M4Na2V10O28 · 10H2O compounds were shown to be isostructural with triclinic crystals (Z= 1, space group P $ \bar 1 $ \bar 1 ), and their unit cell parameters were estimated.  相似文献   

18.
The partial mixing enthalpies of the components (Δm $ \bar H $ \bar H i ) of the Ni-Ga melts were measured using the high-temperature isoperibolic calorimetry at 1770 ± 5 K in wide concentration interval. The limiting partial mixing enthalpy of gallium in a liquid nickel (Δm $ \bar H $ \bar H Ga) is −95.5 ± 19.8 kJ mol−1, and similar function of nickel in liquid gallium (Δm $ \bar H $ \bar H Ni) is −74.5 ± 16.4 kJ mol−1. The integral mixing enthalpy of liquid alloys of this system was calculated from partial enthalpies for the whole concentration area (Δm H min = −32.1 ± 2.7 kJ mol−1 at x Ni = 0.5). The Δm H value of liquid nickel-gallium alloys independence of the temperature is confirmed. Enthalpies of formation of liquid (Δm H) phases of Ni-Ga system were compared with ones for solid (Δf H) phases of this system. An analysis of d-metals influence on formation energy of Ga-d-Me melts was made using the values of Δf H for intermediate phases of these systems. The article was translated by the authors.  相似文献   

19.
《Comptes Rendus Chimie》2003,6(3):377-383
The three-dimensional cyano-bridged bimetallic compound of formula [{Co(H2O)2}2Mo(CN)8]·4 H2O is described. The single-crystal X-ray structural determination revealed that the compound has a polymeric structure based on a network of [MoIV(CN)8] units and CoII ions. Each Mo(CN)8 building block is linked to Co ions through its eight CN ligands and each CoII centre is connected to four Mo units forming a highly symmetrical three-dimensional framework with square-shaped channels running through the structure. The magnetic behaviour in the temperature range 2–300 K and spectroscopic data are reported as well. To cite this article: F. Tuna et al., C. R. Chimie 6 (2003).  相似文献   

20.
Evaporation of aqueous ammonia solutions of K7[Mo4Te4(CN)12]·12H2O or K6[W4Te4(CN)12]·5H2O, copper(ii) chloride, and ethylenediamine afforded the isostructural heterometallic complexes [{Cu(en)2}2{Cu(en)2(NH3)}{M4Te4(CN)12}]·5H2O (M = Mo or W), which were characterized by IR and ESR spectroscopy and X-ray diffraction analysis.  相似文献   

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