Characterisation and cryomagnetic study of a hydrothermally synthesised hydrogen bonded L–M–L type co-ordination polymer

A ligand–metal–ligand type co-ordination polymer [Ni (C₆H₁₂N₄)(NCS)₂(H₂O)₂] _n has been synthesised under controlled hydrothermal conditions. Here 1,3,5,7-tetraazatricyclo[3.3.1]decane [or hexamethylenetetramine (hmt)] has been used as a μ-(N,N′) bidentate spacer molecule. The prepared polymeric complex has been characterised by elemental and spectral analyses. The structure has been confirmed by a single crystal X-ray diffraction study. Magneto-structural correlation has been drawn from cryomagnetic susceptibility measurements (2–300 K) which unequivocally reflects very weak magnetic spin interactions among the long distant octahedral Ni(II) metal centres mediated by hmt and weak hydrogen bonding interactions between the adjacent zigzag one-dimensional polymeric chains carrying into a two-dimensional infinite polymeric framework.     

Synthesis and Crystal Structure of Complex of Sodium Perrhenate with Tetraethyl p-tert-Butylcalix[4]arene Tetraacetate

Recently,theconformationofthecalixarenehasbeenshowntobeimportantincontrollingtheseIectivityofthereceptor.Forexample,sodiumioncouldbeboundverystronglybyesterderivativesofcalix[4]areneintheconeconformationl.Wehavefoundthatinthepresenceofcertainamountofsodiumion,microamountofReO4-canbequantitativelyextractedintol,2-dichloroethanebytheligandtetraethylp-tert-butylcalix[4]arenetetraacetate(L).ItshowsthatthepresenceofNa inaqueoussolutioncanpromotetheformationofhydrophobiccomplex[NaL] .ReO'-whichc…     

Umsetzungen von Ferrocenol und 1,1′-Ferrocendiol mit Cyclotriphosphazenen,P3N3F6 und P3N3Cl6

Reactions of Ferrocenol and 1,1′-Ferrocendiol with Cyclotriphosphazenes, P₃N₃F₆ and P₃N₃Cl₆ The hexahalogeno-cyclotriphosphazenes, P₃N₃X₆ (X ? F ( 1 a ), Cl ( 1 b )), react with ferrocenol (FcOH) in a molar ratio 1 : 1 to give the ferrocenoxy derivatives, FcO[P₃N₃X₅] (X ? F ( 3 a ), Cl ( 3 b )); in an analogous manner the tetrameric ring P₄N₄Cl₈ ( 2 b ) is converted to FcO[P₄N₄Cl₇] ( 4 b ).

1 Abkürzungen: Fc = Ferrocenyl, (C₅H₅)Fe(C₅H_4?); fc = 1,1′-ferrocendiyl, Fe(C₅H_4?)₂; rc = 1,1′-ruthenocendiyl, Ru(C₅H_4?)₂. Fluorphosphazene werden mit a , Chlorphosphazene mit b gekennzeichnet.

With 1,1′-ferrocenediol, (fc(OH) ₂ ), the cyclo triphosphazenes react in a molar ratio 1 : 1 to produce fcO ₂ [P ₃ N ₃ X ₄ ] (X ? F ( 5 a ), Cl ( 5 b )). According to the x-ray structure analysis, the 1,1′-ferrocenediolato group in 5 a , b is bound to two different phosphorus atoms. On the contrary, the 1,1′-ferrocenedithiolato- and 1,1′-ferrocenediselenolato units in fcS ₂ [P ₃ N ₃ X ₅ ] (X ? F ( 6 a ), Cl ( 6 b )) and fcSe ₂ [P ₃ N ₃ X ₅ ] (X ? F ( 7 a ), Cl ( 7 b )) are attached to only one phosphorus atom, and spirocyclic 1,3-dichalcogena-2-phospha-[3]ferrocenophanes are formed. All new products have been characterized on the basis of their ¹ H, ¹³ C and ³¹ P NMR as well as EI mass spectra. The molecular structures of 5 a , b and 6 a have been determined by x-ray structure analyses.     

Syntheses and Structures of Two New Cu/Nb/pyrazine Complexes: Three dimensional CuNb(pyz)2OF5 · (pyz)(H2O) and two dimensional [Cu(pyz)2.5]+ [NbF6]− · (pyz)

Crystals of CuNb(pyz)₂OF₅ · (pyz)(H₂O) ( 1 ) and [Cu(pyz)_2.5]⁺ [NbF₆]^? · (pyz) ( 2 ) were grown (150°C and autogeneous pressures) from CuO, 1/2(Nb₂O₅), (HF)_x · pyridine, and H₂O in excess pyrazine. Light blue single crystals of ( 1 ) are orthorhombic, crystallizing in space group Cccm (No. 66), with a = 14.547(1) Å, b = 16.135(2) Å, c = 13.803(2) Å, and Z = 8. The structure of ( 1 ) contains corner shared [Cu(pyz)_4/2F_2/2]⁺, [Cu(pyz)_4/2O_2/2], and [NbF₄O_1/2F_1/2]^?0.5 octahedra. Orange crystals of ( 2 ) are monoclinic, crystallizing in space group C2/c (No. 15), with a = 11.792(8) Å, b = 17.123(3) Å, c = 17.051(5) Å, β = 90.04(4)°, and Z = 8. The structure of ( 2 ) contains puckered rings of corner shared [Cu(pyz)(pyz)_3/2]⁺ tetrahedra and isolated [NbF₆]^? anions within the rings.     

刚柔相嵌液晶高分子的赝二级相变温度

讨论了刚柔相嵌液晶高分子的向列相一各向同性相转变与其分子结构的关系．给出了该一级相变的赝二级相变温度Ｔ＊与这类液晶高分子的液晶基元和间隔基的长度、柔顺性（相关长度）以及它们之间的相互作用的关系的解析表示式．分析了液晶基元与间隔基连接处的表观弯曲（接口效应）对Ｔ＊的影响．文中的结论与实验相符．     

Zirconiumphthalocyanine: Darstellung und Eigenschaften chloridhaltiger Phthalocyanine des drei- und vierwertigen Zirconiums; Kristallstruktur von cis-Di(triphenylphosphin)iminium-tri(chloro)phthalocyaninato(2–)zirconat(IV)-di(dichlormethan)

Zirconiumphthalocyanines: Synthesis and Properties of Chloride Ligated Phthalocyanines of Ter- and Quadrivalent Zirconium; Crystal Structure of cis-Di(triphenylphosphine)iminium-tri(chloro)phthalocyaninato(2–)zirconate(IV)-di(dichloromethane) cis-Di(chloro)phthalocyaninato(2–)zirconium(IV) is obtained by the reaction of ZrCl₄ with phthalodinitrile in 1-chloronaphthaline at 230°C. It reacts with molten di(triphenylphosphine)iminiumchloride ((PNP)Cl) yielding cis-di(triphenylphosphine)iminium-tri(chloro)phthalocyaninato(2-)zirconate(IV), cis-(PNP)[ZrCl₃Pc^2?]. This crystallizes with two molecules of dichloromethane in the monoclinic space group P2₁/n with the lattice constants a = 15.219(4) Å, b = 20.262(10) Å, c = 20.719(4) Å, b? = 93.46(2)°, Z = 4. The seven coordinated Zr atom is situated in a “square base-trigonal cap” polyhedron. The plane of the three chlorine atoms runs parallel to the plane of the four isoindole nitrogen atoms N_iso. The Zr–Cl distances range from 2.49 to 2.55 Å, the Zr? N_iso distances from 2.26 to 2.29 Å. Due to ion packing effects the Pc^2? ligand shows an asymmetrical convex distortion. The PNP cation adopts the bent conformation. The P? N? P angle is 139°, the P? N distance 1.58 Å. As confirmed by the cyclovoltammograms cis-(PNP)[ZrCl₃Pc^2?] is oxidized (anodically or chemically by Cl₂) to yield cis-tri(chloro)phthalocyaninato(1–)zirconium(IV) and reduced (cathodically or chemically by [BH₄]^?) yielding chlorophthalocyaninato(2–)zirconium(III) and cis-di(triphenylphosphine)iminium-di(chloro)phthalocyaninato(2–)zirconate(III). The optical spectra show the typical π–π*-transitions of the Pc^2? resp. Pc^? ligand not much affected by the different states of oxidation and coordination of zirconium. The same is true for the vibrational spectra of the Pc^2? resp. Pc^? ligand. In the f.i.r. spectra between 350 and 150 cm^?1 the asym. and sym. Zr? Cl stretching and Cl? Zr? Cl deformation vibration as well as the asym. Zr? N stretching vibration of the [ZrCl_xN₄] skeleton (x = 1–3) is assigned.     

DySBr und DySI – Synthese,Kristallstruktur und Magnetismus

DySBr and DySI – Synthesis, Crystal Structure, and Magnetism By reaction of Dy₂S₃ with Dy metal and Br₂ (I₂) at 750°C (900°C), single phase crystalline DySBr (DySI) has been synthesized. Crystal structure refinement of DySBr confirms the FeOCl-type structure (R = 0.049; space group Pmmn, Z = 2, lattice parameters (in Å): a = 5.349(2), b = 4.079(2), c = 8.066(2)) which is also ascertained for DySI (R = 0.059; lattice parameters (in Å): a = 5.320(2), b = 4.168(1), c = 9.224(5)). The magnetic susceptibilities (temperature range 3.4 K – 295 K) can be described on the basis of simple models (cubic crystal field, molecular field approximation) above 5 K and 15 K respectively. The deviations at low temperature are assumed to be related essentially to Dy—Dy exchange interactions which are not adequately described with the molecular field approach.     

Die Gadoliniumcarbidhalogenide Gd4C2X3 (X = Cl,Br)

The Gadolinium Carbide Halides, Gd₄C₂X₃ (X = Cl, Br) The compounds Gd₄C₂X₃ (X = Cl, Br) and Tb₄C₂Br₃ have been prepared by reaction of the metals (RE), REX₃, and C in sealed Ta capsules at 1 100° and 1 300°C, respectively. Monophasic samples of Gd₄C₂Br₃ and Tb₄C₂Br₃ were obtained by reacting stoichiometric mixtures of the starting materials for five days. The needle shaped crystals are bronze-coloured and sensitive to air and moisture. Gd₄C₂X₃ crystallizes in the space group Pnma (No. 62) with lattice constants a = 1 059.6(4), b = 368.4(1), c = 1 962.7(8) pm (Gd₄C₂Cl₃), a = 1 084.4(1), b = 373.0(1), c = 2 036.1(1) pm (Gd₄C₂Br₃). According to Guinier photographs, Tb₄C₂Br₃ is isotypic (a = 1 074.3(2), b = 370.6(1), c = 2 019.4(1) pm). In the crystal structure C is octahedrally coordinated by Gd. The Gd₆ octahedra are linked via common edges to form corrugated layers. The X-anions coordinate all free edges and corners of these layers and connect them via Xⁱ? Xⁱ contacts parallel [001]. Gd₄C₂Br₃ shows metallic conductivity. The magnetic susceptibility follows at high temperatures a Curie Weiss law with an effective moment of 7.95 μ_B. At temperatures below 50 K antiferromagnetic order is observed.     

Solid－state Synthesis at Low－heating Temperature and Crystal Structure of a Dinuclear Molybdenum Complex with Oxalate Ligand［Bu_4N］_2［Mo_2O_2（OH）_2Cl_4（C_2O_4）］

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Synthesis and X-ray crystal structure of oxamido-bridged heterobinuclear Ni(Ⅱ)-Cu(Ⅱ) complexes

The two complexes [Ni(oxen)Cu(L)2](ClO4)2.xH2O (L=2,2'-bipyridyl(bpy), 1,10-phenanthroline(phen)) have been synthesized, where oxen is N,N'-bis(2-aminoethyl)oxamido di-anion. The crystal structure of [Ni(oxen)Cu(bpy)2](ClO4)2.CH3OH has been determined by X-ray diffraction method. The crystal is triclinic system, space group P1 with a=12.179(1),b=12.298(2), c=11.476(2) A, a=97.57(1), B=97.52(1), 7=80.29(2), V=1669.04(67) A3, Z=2, Dcalcd=1.667 g/cm3. The structure has been refined to final R of 0.076 and Rw of 0.080, respectively. The complexes have an extended oxamido-bridged structure and consist of Ni(Ⅱ) ion in a square planar environment and Cu(Ⅱ) ion in a distorted octahedral environment.