Tellurium-bridged manganese carbonyl clusters: synthesis and structural transformations of [Te4Mn3(CO10]-, [Te2Mn3(CO)9]2-, [Te2Mn3(CO)9]-, and [Te2Mn4(CO)12]2-

The reactions of appropriate ratios of K2TeO3 and [Mn2(CO)10)] in superheated methanol solutions lead to a series of novel cluster anions [Te4Mn3(CO)10] (1), [Te2Mn3(CO)9]2- (2), [Te2Mn3(CO)9]- (3), and [Te2Mn4(CO)12]2- (4). When cluster 1 is treated with [Mn2(CO)10]/KOH in methanol, paramagnetic cluster 2 is formed in moderate yield. Cluster 2 is oxidized by [Cu(MeCN)4]BF4 to give the closo-cluster [Te2Mn3(CO)9]- (3), while treatment of 2 with [Mn2(CO)10]/KOH affords the closo-cluster 4. IR spectroscopy showed that cluster 1 reacted with [Mn2(CO)10] to give cluster 4 via cluster 2. Clusters 1-4 were structurally characterized by spectroscopic methods or/and X-ray analyses. The core structure of 1 can be described as two [Mn(CO)3] groups doubly bridged by two Te2 fragments in a mu2-eta2 fashion. Both [Mn(CO)3] groups are further coordinated to one [Mn(CO)4] moiety. Cluster 2 is a 49 e- species with a square-pyramidal core geometry. While cluster 3 displays a trigonal-bipyramidal metal core, cluster 4 possesses an octahedral core geometry.     

A family of calix[4]arene-supported [Mn(III)2Mn(II)2] clusters

In the cone conformation calix[4]arenes possess lower-rim polyphenolic pockets that are ideal for the complexation of various transition-metal centres. Reaction of these molecules with manganese salts in the presence of an appropriate base (and in some cases co-ligand) results in the formation of a family of calixarene-supported [Mn(III)(2)Mn(II)(2)] clusters that behave as single-molecule magnets (SMMs). Variation in the alkyl groups present at the upper-rim of the cone allows for the expression of a degree of control over the self-assembly of these SMM building blocks, whilst retaining the general magnetic properties. The presence of various different ligands around the periphery of the magnetic core has some effect over the extended self-assembly of these SMMs.     

Structural and physical characterization of tetranuclear [Mn(II)3Mn(IV)] and [Mn(II)2Mn(III)2] valence-isomer manganese complexes

Two tetranuclear Mn complexes with an average Mn oxidation state of +2.5 have been prepared. These valence isomers have been characterized by a combination of X-ray crystallography, X-ray absorption spectroscopy, and magnetic susceptibility. The Mn(II)3Mn(IV) tetramer has the Mn ions arranged in a distorted tetrahedron, with an S = 6 ground spin state, dominated by ferromagnetic exchange among the manganese ions. The Mn(II)2Mn(III)2 tetramer also has a distorted tetrahedral arrangement of Mn ions but shows magnetic behavior, suggesting that it is a single-molecule magnet. The X-ray absorption near-edge structure (XANES) spectra for the two complexes are similar, suggesting that, while Mn XANES has sufficient sensitivity to distinguish between trinuclear valence isomers (Alexiou et al. Inorg. Chem. 2003, 42, 2185), similar distinctions are difficult for tetranuclear complexes such as that found in the photosynthetic oxygen-evolving complex.     

Incorporating transition metal complexes into tetrathioarsenates(V): syntheses, structures, and properties of two unprecedented [Mn(dien)2]n[Mn(dien)AsS4]2n.4nH2O and [Mn(en)3]2[Mn(en)2AsS4][As3S6

Two transition-metal tetrathioarsenate complexes, [Mn(dien)(2)](n)[Mn(dien)AsS(4)](2n).4nH(2)O (1) with one-dimensional water chain and [Mn(en)(3)](2)[Mn(en)(2)AsS(4)][As(3)S(6)] (2) with mixed-valence As(3+)/As(5+) character, have been synthesized and structurally characterized. The tetrathioarsenate(V) anion acts as a novel mu(2)-eta(1),eta(2) ligand in 1 and as a chelating ligand in 2. The two compounds exhibit intriguing semiconducting properties (E(g) = 2.18 eV (1), 2.48 eV (2)) and strong photoluminescence with the emission maximum occurring around 440 nm.     

3D porous and 3D interpenetrating triple framework structures constructed by aurophilicity-coordination interplay in [Mn[Au(CN)2]2(H2O)2]n and [KFe[Au(CN)2]3]n

Two cyano-bridged heterobimetallic coordination polymers [Mn[Au(CN)2]2(H2O)2]n (1) and [KFe[Au(CN)2]3]n (2), have been synthesized from [Au(CN)2]- building blocks and structurally characterized. In both complexes aurophilicity play an important role in determining the 3D open microporous framework and the interpenetrating triple framework for 1 and 2, respectively. Both aqueous solutions of 1 and 2 display interesting luminescent properties.     

An Unusual Product from the Reaction of C(PPh3)2 with [Mn2(CO)10]: Formation and Crystal Structure of [Mn(OPPh3)2{O2CC(PPh3)2}2][Mn(CO)5]2

The carbodiphosphorane C(PPh₃)₂ ( 1 ) reacts with [Mn₂(CO)₁₀] in THF to produce quantitatively the salt‐like complex (HC{PPh₃}₂)[Mn(CO)₅] ( 2 ) as THF solvate. If the reaction is carried out in 1,2‐dimethoxyethane (DME) small amounts of [Mn(OPPh₃)₂{O₂CC(PPh₃)₂}₂][Mn(CO)₅]₂ ( 3 ) as DME solvate along with solvent free 2 as the main product were isolated. Proton abstraction from the solvent led to the formation of 2 ; the ligands OPPh₃ and O₂CC(PPh₃)₂}₂ of 3 are the results of a side reaction from [Mn₂(CO)₁₀] and 1 in a Wittig type manner. From the reaction in benzene small amounts of 3 were also obtained, crystallizing as benzene solvate 3· 4C₆H₆. The crystal structures of 2· THF, 2 , 3· 1.75DME and 3· 4C₆H₆ are reported. The compounds are further characterized by IR and ³¹P NMR spectroscopy.     

Isotype Strukturen einiger Hexaamminmetall(II)-halogenide von 3d-Metallen: [V(NH3)6]I2, [Cr(NH3)6]I2, [Mn(NH3)6]Cl2, [Fe(NH3)6]Cl2, [Fe(NH3)6]Br2, [Co(NH3)6]Br2 und [Ni(NH3)6]Cl2

The Structures of some Hexaammine Metal(II) Halides of 3 d Metals: [V(NH₃)₆]I₂, [Cr(NH₃)₆]I₂, [Mn(NH₃)₆]Cl₂, [Fe(NH₃)₆]Cl₂, [Fe(NH₃)₆]Br₂, [Co(NH₃)₆]Br₂ and [Ni(NH₃)₆]Cl₂ Crystals of yellow [V(NH₃)₆]I₂ and green [Cr(NH₃)₆]I₂ were obtained by the reaction of VI₂ and CrI₂ with liquid ammonia at room temperature. Colourless crystals of [Mn(NH₃)₆]Cl₂ were obtained from Mn and NH₄Cl in supercritical ammonia. Colourless transparent crystals of [Fe(NH₃)₆]Cl₂ and [Fe(NH₃)₆]Br₂ were obtained by the reaction of FeCl₂ and FeBr₂ with supercritical ammonia at 400°C. Under the same conditions orange crystals of [Co(NH₃)₆]Br₂ were obtained from [Co₂(NH₂)₃(NH₃)₆]Br₃. Purple crystals of [Ni(NH₃)₆]Cl₂ were obtained by the reaction of NiCl₂ · 6H₂O and NH₄Cl with aqueous NH₃ solution. The structures of the isotypic compounds (Fm3 m, Z = 4) were determined from single crystal diffractometer data (see “Inhaltsübersicht”). All compounds crystallize in the K₂[PtCl₆] structure type. In these compounds the metal ions have high-spin configuration. The orientation of the dynamically disordered hydrogen atoms of the ammonia ligands is discussed.     

3D Organic–Inorganic Perovskite Ferroelastic Materials with Two Ferroelastic Phases: [Et3P(CH2)2F][Mn(dca)3] and [Et3P(CH2)2Cl][Mn(dca)3]

Organic–inorganic hybrid perovskite-type multiferroics have attracted considerable research interest owing to their fundamental scientific significance and promising technological applications in sensors and multiple-state memories. The recent achievements with divalent metal dicyanamide compounds revealed such malleable frameworks as a unique platform for developing novel functional materials. Herein, two 3D organic–inorganic hybrid perovskites [Et₃P(CH₂)₂F][Mn(dca)₃] ( 1 ) and [Et₃P(CH₂)₂Cl][Mn(dca)₃] ( 2 ) (dca=dicyanamide, N(CN)₂⁻) are presented. Accompanying the sequential phase transitions, they display a broad range of intriguing physical properties, including above room temperature ferroelastic behavior, switchable dielectricity, and low-temperature antiferromagnetic ordering (T_c=2.4 K for both 1 and 2 ). It is also worth noting that the spontaneous strain value of 1 is far beyond that of 2 in the first ferroelastic phase, as a result of the precise halogen substitution. From the point view of molecular design, this work should inspire further exploration of multifunctional molecular materials with desirable properties.     

Dipotassium trimanganese(II) tetrakis(hydrogenphosphite), K2[Mn3(HPO3)4]

The title compound is a new mixed alkali/3d metal phosphite. It exhibits a layered structure formed by linear Mn₃O₁₂ trimer units which contain face‐sharing MnO₆ octahedra interconnected by (HPO₃)²⁻ phosphite oxoanions. The K⁺ cations located between the anionic [Mn₃(HPO₃)₄]²⁻ sheets are ninefold coordinated. The presence of the alkaline ion leads to the highest symmetry and shortest interlayer distance compared with two previous compounds showing the same anionic framework and having ammonium salts as cations. The compound crystallizes in the space group Rm, with two crystallographically independent Mn atoms occupying sites of m and 3m symmetry. All the other atoms, except for the phosphite O atoms, are located on special positions with 3m symmetry.     

Novel K/Mn phosphate hydrates,K2Mn3(H2O)2[P2O7]2 and KMn(H2O)2[Al2(PO4)3]: hydrothermal synthesis and crystal chemistry

Two novel K/Mn phosphate hydrates, namely, dipotassium trimanganese dipyrophosphate dihydrate, K₂Mn₃(H₂O)₂[P₂O₇]₂, (I), and potassium manganese dialuminium triphosphate dihydrate, KMn(H₂O)₂[Al₂(PO₄)₃], (II), were obtained in the form of single crystals during a single hydrothermal synthesis experiment. Their crystal structures were studied by X‐ray diffraction. Both new compounds are members of the morphotropic series of phosphates with the following formulae: A₂M₃(H₂O)₂[P₂O₇]₂, where A = K, NH₄, Rb or Na and M = Mn, Fe, Co or Ni, and AM²⁺(H₂O)₂[M³⁺₂(PO₄)₃], where A = Cs, Rb, K, NH₄ or (H₃O); M²⁺ = Mn, Fe, Co or Ni; and M³⁺ = Al, Ga or Fe. A detailed crystal chemical analysis revealed correlations between the unit‐cell parameters of the members of the series, their structural features and the sizes of the cations. It has been shown that a mixed type anionic framework is formed in (II) by aluminophosphate [(AlO₂)₂(PO₄)₂]_∞ layers, with a cationic topology similar to the Si/Al‐topology of the crystal structures of feldspars. A study of the magnetic susceptibility of (II) demonstrates a paramagnetic behaviour of the compound.     

First oxalate-bridged pentanuclear [Cu(L)]3[Mn(ox)3]2 complexes: synthesis and magnetism

Two novel CuII3MnIII2 pentanuclear oxalato complexes have been synthesized and characterized, namely [Cu(L)]3[Mn(ox)3]2 [L = 1,10-phenanthroline(phen) and 2,2-bipyridyl(bipy)] where ox is the oxalate dianion. Based on i.r., elemental analyses and electronic spectra, thesecomplexesareassignedtoextendedoxalato-bridged structures consisting of two manganese(III) ions and three copper(II) ions, in which each manganese(III) has a distorted octahedral environment and each copper(II) ion a distorted square pyramidal environment. The temperature dependance of the magnetic susceptibility for [Cu(phen)]3[Mn(ox)3]2·4H2O was measured over the 4.2–300K range and the observed data indicates antiferromagnetic spin exchange interaction between the CuII and MnIII ions.     

以有机溶剂热生长技术制备金属硫族化合物[Mn(en)_3]PdSe_2及其晶体结构分析

以有机溶剂热生长技术 (solvothermaltechnique) ,即在 180℃乙二胺 (en)溶液中 ,以MnCl3,PdCl2 ,K2 Se在密闭容器中反应 7d ,制备出新的硫族化合物 [Mn(en) 3]PdSe2 ,其阴离子基团为 [PdSe2 ]2 -,阳离子基团为过渡金属Mn与乙二胺 (en)的配合物 :[Mn(en) 3]2 +.以单晶X射线衍射技术解得该晶体结构属正交晶系 ,空间群为Pbcn ,[Mn(en) 3]·PdSe2 (Ⅰ )的晶胞数据 :a =1.1484( 2 ) ,b=1.5 0 5 7( 3 ) ,c =0 .93 62 2 ( 19)nm ,Z =4.     

以有机溶剂热生长技术制备金属硫族化合物 [Mn(en)~3]PdSe~2及其晶体结构分 析

以有机溶剂热生长技术(solvothermaltechnique),即在180℃乙二胺(en)溶液中,以MnCl~3,PdCl~2,K~2Se在密闭容器中反应7d,制备出新的硫族化合物[Mn(en)~3]PdSe~2,其阴离子基团为[PdSe~2]^2^-,阳离子基团为过渡金属Mn与乙二胺(en)的配合物：[Mn(en)~3]^2^+。以单晶X射线衍射技术解得该晶体结构属正交晶系,空间群为Pbcn,[Mn(en)~3]PdSe~2(Ⅰ)的晶胞数据：a=1.1484(2),b=1.5057(3),c=0.93622(19)nm,Z=4。     

1-D and 2-D homoleptic dicyanamide structures, [Ph4P]2[CoII[N(CN)2]4] and [Ph4P][M[N(CN)2]3] (M = Mn, Co)

The homoleptic complexes [Ph(4)P](2)[Co[N(CN)(2)](4)] and [Ph(4)P][M[N(CN)(2)](3)] [M = Co, Mn] have been structurally as well as magnetically characterized. The complexes containing [M[N(CN)(2)](4)](2-) form 1-D chains, which are bridged via a common dicyanamide ligand in [M[N(CN)(2)](3)](-) to form a 2-D structure. The five-atom [NCNCN](-) bridging ligands lead to weak magnetic coupling along a chain. The six [NCNCN](-) ligands lead to a (4)T(1g) ground state for Co(II) which has an unquenched spin-orbit coupling that is reflected in the magnetic properties. Long-range magnetic ordering was not observed in any of these materials.