Tantalcluster in oxidischer Matrix – Synthese und Strukturen der gemischtvalenten Oxotantalate M2–δTa15O32 (M = K,Rb (δ = 0); M = Sr (δ = 0.15), Ba (δ = 0.12))

Tantalum Cluster in an Oxidic Matrix – Synthesis and Structures of Mixed-Valence Oxotantalates M_2–δTa₁₅O₃₂ (M = K, Rb (δ = 0); M = Sr (δ = 0.15), Ba (δ = 0.12)) The mixed-valent oxides Sr_1.85Ta₁₅O₃₂ ( 1 ), Ba_1.88Ta₁₅O₃₂ ( 2 ), K₂Ta₁₅O₃₂ ( 3 ), Rb₂Ta₁₅O₃₂ ( 4 ) were prepared from appropriate mixtures of Ta₂O₅, tantalum and the corresponding carbonate at 1520–1670 K in sealed tantalum tubes. According to X-ray single crystal structure analyses the oxides crystallize in the space group R3¯, Z = 1. The lattice parameters in the hexagonal setting are a = 777.36(11), c = 3516.2(7) pm for 1 , a = 778.87(11), c = 3548.1(7) pm for 2 , a = 780.7(2), c = 3573.1(11) pm for 3 , and a = 781.90(11), c = 3593.0(7) pm for 4 . The oxide ions form a defect dense packing with the layer sequence chhhh. Anti-cuboctahedral sites are completely occupied by the alkali metal cations. The alkaline earth cations occupy 92 to 94% of such sites; they are displaced from the centres. Smaller voids are located in the centres of the cuboctahedral Ta₆O₁₂ clusters forming the characteristic structural unit of these low-valent oxotantalates. In case of 3 and 4 the clusters have 13 electrons, in case of 1 and 2 they have close to 15 electrons available for Ta–Ta-bonding. Moreover, the structures of the alkali and alkaline earth metal compounds differ notably with respect to the spectrum of Ta–O and Ta–Ta distances in the Ta₃O₁₃ octahedra triples forming another characteristic structural unit for these oxides. Such differences are traced back to distinct local charge balances for the uni- and divalent cations. The oxides 2 , 3 are semiconductors with band gaps ranging from 130 to 360 meV.     

FeNCN and Fe(NCNH)2: Synthesis,Structure, and Magnetic Properties of a Nitrogen‐Based Pseudo‐oxide and ‐hydroxide of Divalent Iron

Iron man challenge : Iron carbodiimide, FeNCN, and its precursor iron (bis)monohydrocyanamide, Fe(NCNH)₂, have been synthesized and physically characterized. Both FeNCN and Fe(NCNH)₂ exhibit nitrogen‐mediated antiferromagnetic superexchange interactions with reduced magnetic moments very similar, but not identical, to the correlated 3d oxides.

     

Synthesis,Crystal Structure and Magnetic Properties of a Novel Heterobimetallic Rhenium(IV)–Dysprosium(III) Chain

The use of the mononuclear rhenium(IV) precursor [ReBr₅(H₂pydc)]^? (H₂pydc=3,5‐pyridinedicarboxylic acid) as a metalloligand towards dysprosium(III) afforded the first heterobimetallic Re^IV–Dy^III complex. Crystal structures and static and dynamic magnetic properties of both rhenium‐containing species are reported herein. The 5d–4f compound shows an extended 1D structure and the AC magnetic measurements reveal frequency dependence at low temperature suggesting slow relaxation of the magnetization.     

Sr3GdRhO6 - The First RhIII Compound with the K4CdCl6 Structure-type: Synthesis,Crystal Structure,and Magnetic Properties

The compound Sr₃GdRhO₆ has been synthesized and structurally characterized by Rietveld refinement of powder X-ray diffraction data. (space group R3 c; Z = 6; a = 9.7840(5) Å; c = 11.4196(7) Å) This compound is isostructural with K₄CdCl₆. The structure consists of infinite one-dimensional chains of alternating face-shared RhO₆ octahedra and GdO₆ trigonal prisms. The strontium cations are located in a distorted square antiprismatic environment. Magnetic susceptibility data show that Sr₃GdRhO₆ obeys the Curie law with η_eff = 7.80 B.M., consistent with an oxidation state of +3 for both rhodium and gadolinium.     

新型氰基桥联配位聚合物[Ni(en)2]2[Ni(CN)4]2·5H2O的合成、晶体结构和磁性质

分子组装在材料科学、催化和生物化学中具有潜在的应用前景,所以分子组装引起了化学、固体物理学和生物学等领域科学家们的普遍关注犤1犦。分子组装常用的方法是使用具有配位能力的金属配合物作为建筑块与过渡金属阳离子反应。氰基桥联多核配合物由于其结构的多样性和具有特别优异的磁性质,近10年来在配位化学领域倍受关注犤2～8犦。在系列配合物犤M(en)2犦犤Ni(CN)4犦(M=Ni,Cu,Zn,Cd等)中,犤Cu(en)2犦犤Ni(CN)4犦和犤Cd(en)2犦犤Ni(CN)4犦的晶体结构已经通过单晶衍射的方法测得犤9,10犦。在犤Cu(en)2犦犤Ni(CN)4犦中,Cu原子为六配…     

A New Dinuclear Copper (II) Complex of a Bis‐macrocyclic Ligand: Synthesis,Characterization, Crystal Structure and Magnetic Properties

A new dinuclear Cu(II) complex, [Cu₂L(N₃)₂](ClO₄)₁.₅ (OH)_4.5 · 2H₂O 0.5C₂H₅OH (1), of a bis‐macrocyclic ligand, 2,6‐bis(l,4,7,10‐tetraazacyclododecan‐10‐ylmethyl)‐methoxybenzene (L), has been synthesized, characterized and structurally determined by X‐ray diffraction analysis. Complex 1 crystallizes in orthorhombic crystal system, Pca2(l) space group with a = 1.5371(3), b = 1.6641(3), c = 3.0950(6) nm, V = 7.917(3) nm³, F_w = 904.62, Z=8, D_c= 1.529 g/cm³ and final R = 0.0568, wR = 0.1406 for 10410 observed reflections with I≥2σ (I). Both Cu(II) centers in the structure are coordinated by four nitrogen atoms of 1,4,7, 10‐tetraazacyclododecane (cyclen) and a nitrogen donor of the axial azide anion. Each Cu(II) center is in a square‐pyramidal coordination environment, and the intra‐and nearest inter‐molecular Cu? Cu nonbonding distances are 0.9855 and 0.7298 nm, respectively. Variable temperature magnetic susceptibility measurements in the range of 4.2–300 K indicate mat there exists weak intra‐ and inter‐molecular antiferromagnetic coupling between the Cu(II) centers with 27= ?4.2 cm^?1 and Θ = ?0.47 K.     

Synthesis, Crystal Structure and Magnetic Properties of a New Zn(II)-Nitronyl Nitroxide Complex

A new complex [Zn(NIT-1'-MeBzIm)Cl2(H2O)] (NIT-1'-MeBzIm = 2-{2'-[(l'- methyl)benzimidazolyl]}-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been prepared and structurally characterized by X-ray diffraction method. Crystal data: monoclinic, space group P21/n, Z = 4, C15H21Cl2N4O3Zn, Mr = 441.63, a = 7.2225(10), b = 30.849(4), c = 8.8758(13) , β = 103.904(2)°, V = 1919.6(5) 3, Dc = 1.528 g/cm3, μ(MoKα) = 1.579 mm1, F(000) = 908, R = 0.0436 and wR = 0.1029 for 2456 observed reflections with I > 2σ(I). X-ray analysis reveals that the Zn(II) ion is four-coordinated with a distorted tetrahedron. There also exist H-bonds, π-π piling interactions and weak intermolecular contacts between the NO groups which form a mutual stagger 3-D network configuration. Magnetic investigation reveals that there exists intermolecular antiferro- and ferromagnetic interactions in the title complex.     

Synthesis, Crystal Structure and Magnetic Properties of Cobalt(II) Complex Involving Imino Nitroxide Radicals

1 INTRODUCTION The synthesis and study of transition metal com-plexes incorporating organic free radicals have arou-sed great interest in the field of molecular magne-tism[1]. Nitronyl nitroxide radicals (NITR), stable or-ganic radicals, have been widely used as molecularunits in the design and construction of magnetic ma-terials[2～5]. These radicals are especially attractivedue to that their donor atoms can assemble an exten-ded coordination geometry with changing magneticcoupling. A…     

三元混配配合物[Ni(PMBP-sal)(py)]的合成、表征与晶体结构

合成了混配配合物[Ni(PMBP-sal)(py)]，(PMBP：1-苯基-3-甲基-4-苯亚甲基吡唑啉酮-5，sal：水杨酰肼，py：吡啶)，并用元素分析，IR光谱，紫外可见吸收光谱，循环伏安和单晶X-射线衍射进行表征。结构分析表明N-(1-苯基-3-甲基-4-苯亚甲基吡唑啉酮-5)-水杨酰肼和吡啶与Ni(Ⅱ)配位形成略微畸变的平面正方形化合物。     

Synthesis and Crystal Structure of Di-n-butyltin（Ⅳ） Complex with 2-Oxo-propionic Acid （4-Pyridinecarbonyl） Hydrazone

The novel complex di‐n‐butyltin(IV) 2‐oxo‐propionic acid (4‐pyridinecarbonyl) hydrazone, (n‐C₄H₉)₂Sn‐[O₂CC(CH₃)=N‐N=C(‐O)C₅N‐4] (H₂O) has been synthesized and its structure has been determined by X‐ray diffraction analysis. The complex crystallizes in orthorhombic system with space group Pca2₁. Crystal data: a=2.7540(9) nm, b=0.9676(3) nm, c= 1.5750(5) nm, V=4.197(2) nm³, D_c= 1.444 g/cm³, Z=8. μ= 1.241 mm^?1. F(000)= 1856, R₁=0.0462 and wR₂=0.1001. In the crystals of the title complex, the tin atom is in six‐coordination with a distorted octahedral geometry, three oxygen atoms [O(1), O(3) and O(4)] and one nitrogen atom N(1) forming the equatorial plane and C(10)‐Sn(1)‐C(14) being the axis. Two molecules form a dimer with weak interactions of Sn‐O bonding and hydrogen bonds.     

Synthesis, Crystal Structure and Electrochemical Properties of Complex [Ni(2,2’-bipy)_2(ClC_6H_4COO)(H_2O)](ClO_4)

1 INTRODUCTION Nickel is vital for organism as a trace element and it often acts as component or secondary factor of enzyme. In the latest two decades, biological inor- ganic chemistry of nickel has become one of the hottest fields and the coordination chemistry of nic- kel has made a great progress[1]. Complexes built upon organic aromatic carboxylic acid and metallic ion have attracted chemists’ interest for years due to their potential applications in material, medicine, molecular ele…     

Cs2Cu3MIVF12 (MIV = Zr,Hf) – Kristallstruktur und magnetische Eigenschaften

Cs₂Cu₃M^IVF₁₂ (M^IV = Zr, Hf) – Crystal Structure and Magnetic Behaviour Colourless single crystals of Cs₂Cu₃ZrF₁₂ are obtained by heating the binary fluorides in sealed Pt-tubes under dry argon (solid state reaction, T ≈? 700°C, t ≈? 7–10 d). The compound crystallizes trigonal-rhomboedrical in the space group R3 m-D (Nr. 166); lattice parameters are a = 716.61(6) pm, c = 2 046.4(2) pm, Z = 3 (Four cycle diffractometer data, AED 2). The structure is dominated by layers of corner-sharing, Jahn-Teller-distorted [CuF₆]-Octahedra, which are connected via regular [ZrF₆]-Octahedra to stackings parallel [00.1]. Cs⁺-ions are located in the spacings of the octahedra-network. From powder data Cs₂Cu₃HfF₁₂ with a = 716.32(4) pm, c = 2 048.6(2) pm is isotypic. Both compounds show antiferromagnetic behaviour already at temperatures about 200 K.     

Synthesis, Crystal Structure and Magnetic Properties of a Co(Ⅱ) Complex Containing 2'-(1'- Methyl)benzimidazolyl-substituted Nitronyl Nitroxide

A new complex [Co(NIT-1'-MeBzIm)<,2>Cl<,2>] (NIT-1'-MeBzIm = 2-{2'-[(1'-methyl)- benzimidazolyl] }-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been prepared and structurally characterized by X-ray diffraction method.The complex crystallizes in the monoclinic system, space group C2/c, Z = 4.Crystal data: C<,30>H<38>Cl<,2>CoN<,8>O<,4>, M<,r> = 704.51, a = 17.074(3), b = 21.350(3), c = 11.6962(19) (A), β= 108.879(2)°, V= 4034.3(11) (A)<'3>, D<,c> = 1.160 g/cm<'3>,μ(MoKα) = 0.597 mm<'-1>, F(000) = 1468, R = 0.0422 and wR = 0.1141 for 2577 observed reflections with I > 2σ(I).X-ray analysis reveals that the Co(Ⅱ) ion is six-coordinated with a distorted octahedral geometry.Temperature dependenee of susceptibility measurements shows the existence of antiferromagnetic interactions between the Co(Ⅱ) ion and the radicals (J= -52.88 cm<'-1>).     

Synthesis, Structure and Magnetic Properties of Two New Homotrinuclear Bis(oxamato) Copper(II) Complexes

ＩｎｔｒｏｄｕｃｔｉｏｎＭｏｌｅｃｕｌａｒｍａｇｎｅｔｉｓｍｏｆｐｏｌｙｎｕｃｌｅａｒｃｏｍｐｌｅｘｅｓｉｓｏｆｃｏｎｓｉｄｅｒａｂｌｅｉｎｔｅｒｅｓｔｆｏｒｄｅｓｉｇｎｉｎｇｎｅｗｍａｇｎｅｔｉｃｍａｔｅｒｉａｌｓａｎｄｆｏｒｉｎｖｅｓｔｉｇａｔｉｎｇｔｈｅｒｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎｔｈｅｓｔｒｕｃｔｕｒｅａｎｄｔｈｅｒｏｌｅｏｆｔｈｅｐｏｌｙｍｅｔａｌｌｉｃａｃｔｉｖｅｓｉｔｅｓｉｎｂｉｏｌｏｇｉｃａｌｓｙｓｔｅｍｓ.1 4 Ｊｏｕｒｎａｕｘｅｔａｌ .5ｈａｖｅｒｅｃｅｎｔｌｙｐｒｏｐ…     

Preparation, Crystal Structure and Properties of a Pentametallic 3-Ferrocenyl-2-crotonic acid-Bridged Copper（Ⅱ） Complex

The synthesis and characterization of the copper (II) complex [Cu₂(OOCCH = C(CH₃)Fc)₃(phen)₂]CIO₄ · 2H₂O (1) are reported. The structure of the complex was determined by single‐crystal X‐ray analysis. The compound crystallizes in the monoclinic system, space group Pc, with Z =2, a = 1.2799(4) nm, b =0.9969 (4) nm, c = 2.5228 nm, and β = 91.576 (1) °. The cationic part of 1 indicates a penametallic core in which three 3‐ferrocenyl‐2‐crotonic acid salt (FCA) groups act as (O, O') bridging ligands between two copper (II) ions with a square‐pyramidal environment. Cyclic voltammetric experiments in acetonitrile have been performed mainly to examine the Fe(II) → Fe(III) one‐electron oxidation in FCA and its complex. The variable‐temperature magnetic susceptibility measurements revealed very weak intramolecular anti‐ferromagnetic coupling. Fitting parameters are 2J = ‐0.2 cm^?1, g = 2.114, and θ = 0K.     

Magnetic properties of a new cobalt hydrogen vanadate with a dumortierite‐like structure: Co13.5(OH)6(H0.5VO3.5)2(VO4)6

The magnetic properties of a novel cobalt‐based hydrogen vanadate, Co_13.5(OH)₆(H_0.5VO_3.5)₂(VO₄)₆, are reported. This new magnetic material was synthesized in single‐crystal form using a conventional hydrothermal method. Its crystal structure was determined from single‐crystal X‐ray diffraction data and was also characterized by scanning electron microscopy. Its crystal framework has a dumortierite‐like structure consisting of large hexagonal and trigonal channels; the large hexagonal channels contain one‐dimensional chains of face‐sharing CoO₆ octahedra linked to the framework by rings of VO₄ tetrahedra, while the trigonal channels are occupied by chains of disordered V₂O₄ pyramidal groups. The magnetic properties of this material were investigated by DC magnetic measurements, which indicate the occurrence of antiferromagnetic interactions.     

Synthesis,Characterization, and Crystal Structure of [ReO(Me4tu)4](PF6)3 (tu = thiourea)

A new Re^V oxo complex with tetramethylthiourea, [ReO(Me₄tu)₄](PF₆)₃, has been synthesized by reduction of perrhenate with tin(II) chloride in strongly acidic solution in the presence of excess tetramethylthiourea. The complex has been characterized by elemental analysis and electronic and FTIR spectroscopy. The molecular structure of the compound was determined by X‐ray diffraction methods. The coordination polyhedron is a regular square pyramid with the substituted thiourea sulfur atoms in the equatorial positions [d(Re–S) = 2.339(3) Å] and the oxo ligand located in the summit [d(Re–O) = 1.63(2) Å]. Computational methods were employed to analyze the geometric and electronic structures of tetramethylthiourea and thiourea. Quantum mechanical studies suggest steric hindrance as the reason for the stabilization of the ReO³⁺ center instead of the Re^III one.     

Syntheses, Spectroscopic Properties and Crystal Structures of （2-Cl-C6H4CH2）3SnS2CN（C5H10） and （2-Cl-C6H4CH2）3SnS2CN（C4H9N）

1 INTRODUCTION The chemistry of organotin(IV) complexes was extensively studied due to their biological activity and coordination chemistry[1～7]. More recently, phar- maceutical properties of alkyltin(IV) complexes with dithiocarbamate ligands have bee…     

The First New Hydrogen-Bonded Heterohexanuclear Complex [(salen)Cu]4[(salen)Fe(H2O)2]2(ClO4)2: Molecular and Crystal Structure and Magnetic Properties

The preparation, magnetic properties, and crystal structure of [(salen)Cu]₄[(salen)Fe(H₂O)₂]₂(ClO₄)₂ via hydrogen bonding are described [salen=N,N-ethylenebis (salicylideneiminate)]. Crystals are triclinic, of space group , with cell constants a=12.853(3), b=13.921(3), c=14.251(3) Å, =68.68(3)°, =87.86(3)°, =86.82(3)°, and Z=1. The structure was solved and refined to R=0.064 and R=0.068. The structure comprises the hexanuclear units which result from the linking of four mononuclear fragments [(salen)Cu] and two mononuclear fragment [(salen)Fe(H₂O)]⁺, through Cu -O H -O -Fe -O -H O -Cu hydrogen bonds of coordinating H₂O. In this complex, Fe^III ions are in almost square-planar surroundings. The temperature dependences of the magnetic susceptibilities of the complex have been studied in the 4.2–300 K range, indicating the presence of an antiferromagnetic interactions between metal ions.