[M(4,4'bpy)(N_3)_2]_n(4,4'bpy为4,4'-联吡啶, M=Mn(Ⅱ),Ni(Ⅱ),Cu(Ⅱ),Fe(Ⅱ))的合成、表征、晶体结构和磁性研究

报道了一个由μ-1, 3-N3-和4,4′-联吡啶桥联的配合物{Mn(4,4′bpy)(N3)2}n的合成、晶体结构和磁性. 该配合物具有罕见的脚手架状的三维结构, 磁性测量表明配合物具有弱的反铁磁性J(N3-) = -5.74 cm-1, J(4,4′bpy) = -0.72 cm-1. 同时还报道了其衍生物({Ni(4,4′bpy)(N3)2}n, {Cu(4,4′bpy)(N3)2}n, {Fe(4,4′bpy)(N3)2}n)的合成和表征.     

[M(4,4′bpy)(N3)2]n(4,4′bpy为4,4′-联吡啶, M = Mn(Ⅱ), Ni(Ⅱ), Cu(Ⅱ), Fe(Ⅱ))的合成、表征、晶体结构和磁性研究

报道了一个由--1, 3-N3-和4,4′-联吡啶桥联的配合物{Mn(4,4′bpy)(N3)2}n的合成、晶体结构和磁性. 该配合物具有罕见的脚手架状的三维结构, 磁性测量表明配合物具有弱的反铁磁性J(N3-) = -5.74 cm-1, J(4,4′bpy) = -0.72 cm-1. 同时还报道了其衍生物({Ni(4,4′bpy)(N3)2}n, {Cu(4,4′bpy)(N3)2}n, {Fe(4,4′bpy)(N3)2}n)的合成和表征.     

TATP-铜(Ⅱ)-L-氨基酸配合物的合成、表征及其SOD活性

合成了三种新的配合物[Cu(TATP)(L-Val)(H2O)]ClO4.0.5H2O(1)、[Cu(TATP)(L-Ser)(H2O)]ClO4(2)、[Cu(TATP)(L-Arg)(H2O)]2ClO4.0.5H2O(3)(TATP=1,4,8,9-四氮三联苯,L-Val=L-缬氨酸,L-Ser=L-丝氨酸,L-Arg=L-精氨酸),并通过元素分析、红外光谱、紫外-可见光谱和摩尔电导率对其进行了表征。此外,用改进的氮蓝四唑(NBT)光还原法测定了上述配合物以及配合物[Cu(TATP)(L-Tyr)(H2O)]ClO4.H2O(4)(L-Tyr=L-酪氨酸)对O2-.歧化的催化作用。结果表明,配合物均具有良好的超氧化歧化酶(SOD)活性,在0.2～0.9μmol.L-1浓度范围内抑制率达到50%以上,活性大小按1>3>2>4排列。     

叠氮两端桥连的双核席夫碱铜(Ⅱ)配合物的合成、晶体结构、热稳定性和磁性研究

利用三齿席夫碱配体5-(乙基甲基氨基)-2-[(2-吗啉-4-乙亚胺基)甲基]苯酚(HL)和叠氮化钠以及醋酸铜在甲醇中反应制备了一个新的具有二重轴对称性的叠氮配体两端桥连的双核铜(Ⅱ)配合物[Cu2L2(μ1,3-N3)2]。利用元素分析、红外光谱和X-射线单晶衍射表征了该配合物的结构。配合物的晶体以正交晶系P21212空间群结晶,其晶体学参数a=0.974 6(1),b=1.378 4(2),c=1.504 1(2)nm,V=2.023 3(5)nm3,Z=2,R1=0.063 8,wR2=0.166 8。本文还研究了该配合物的热稳定性和磁性。     

具有单分子磁行为的二维Dy(Ⅲ)-配合物（英文）

在水热条件下,利用刚性配体Hapca(3-氨基吡嗪-2-羧酸)合成了一例基于双核镝结构基元的二维网格配合物[Dy2(apca)4(OH)2(H_2O)2]n(1)。磁性研究表明:该配合物显示铁磁耦合,并具有典型的慢弛豫行为,其弛豫时间τ0=9.47×10-7s,各向异性能垒Ueff/kB=73.7 K,是一例少见的具有单分子磁行为的镧系二维网格配合物。     

具有慢磁驰豫和发光性质的基于多胺酚配体的Dy(Ⅲ)和Zn/Ni-Dy(Ⅲ)配合物

合成了4个新的基于多胺酚配体的Dy(Ⅲ)和Zn/Ni-Dy(Ⅲ)配合物:[Dy(CH_3OCH3)L](1),[Dy2(μ-H2O)L2](2),[Zn2DyL2]ClO4·H2O(3)和[Ni2DyL2]ClO4·H2O (4)(H3L=N,N′,N″-三(3,5-二甲基-2-羟基苯酚)-1,4,7-三氮杂环壬烷)。X射线单晶衍射分析表明,配合物1和2分别为单核和双核Dy(Ⅲ)配合物,3和4为M-Dy(Ⅲ)-M三核配合物(M=Zn (3),Ni (4))。磁性测试表明,配合物1和2具有场诱导的慢磁弛豫行为,且2具有多个磁弛豫过程,配合物3和4中没有观察到明显的慢磁弛豫行为。荧光测试表明,配合物1~3具有Dy(Ⅲ)离子典型的窄带特征发射,由于Ni(Ⅱ)离子的荧光猝灭作用,配合物4没有明显的荧光产生。     

2，2′-联吡啶-3，3′-二羧酸锰(Ⅱ)配合物的合成、晶体结构及性能研究

以2,2′-联吡啶-3,3′-二羧酸(H2L)和1,10-邻菲啰啉(Phen)为配体合成了一个新的锰(Ⅱ)配合物[Mn(H2O)(L)(Phen)2].(H2O)3。该配合物晶体属单斜晶系,空间群P21/c。在配合物中,中心锰(Ⅱ)离子的配位数是6,处于变形的八面体配位环境中。还测定了标题配合物的磁性,荧光和电化学性能,结果表明:在低温下,配合物有反铁磁性;当激发波长为656 nm时,配合物在682 nm附近有一个宽的荧光发射峰;在循环伏安过程中配合物的电子转移是准可逆的,对应的电极反应是Mn髥/Mn(Ⅱ)。     

2,2'-联吡啶-3,3'-二羧酸锰(Ⅱ)配合物的合成、晶体结构及性能研究

以2,2’-联吡啶-3,3’-二羧酸(H2L)和1,10-邻菲啰啉(Phen)为配体合成了一个新的锰(Ⅱ)配合物[Mn(H2O)(L)(Phen)2]· (H2O)3.该配合物晶体属单斜晶系,空间群P21/c.在配合物中,中心锰(Ⅱ)离子的配位数是6,处于变形的八面体配位环境中.还测定了标题配合物的磁性,荧光和电化学性能,结果表明:在低温下,配合物有反铁磁性;当激发波长为656 nm时,配合物在682 nm附近有一个宽的荧光发射峰;在循环伏安过程中配合物的电子转移是准可逆的,对应的电极反应是Mn(Ⅲ)/Mn(Ⅱ).     

具有慢磁驰豫和发光性质的基于多胺酚配体的Dy(Ⅲ)和Zn/Ni-Dy(Ⅲ)配合物（英文）

合成了4个新的基于多胺酚配体的Dy(Ⅲ)和Zn/Ni-Dy(Ⅲ)配合物:[Dy(CH_3OCH_3)L](1),[Dy_2(μ-H_2O)L_2](2),[Zn_2DyL_2]ClO_4·H_2O(3)和[Ni_2DyL_2]ClO_4·H_2O (4)(H_3L=N,N′,N″-三(3,5-二甲基-2-羟基苯酚)-1,4,7-三氮杂环壬烷)。X射线单晶衍射分析表明,配合物1和2分别为单核和双核Dy(Ⅲ)配合物,3和4为M-Dy(Ⅲ)-M三核配合物(M=Zn (3),Ni (4))。磁性测试表明,配合物1和2具有场诱导的慢磁弛豫行为,且2具有多个磁弛豫过程,配合物3和4中没有观察到明显的慢磁弛豫行为。荧光测试表明,配合物1～3具有Dy(Ⅲ)离子典型的窄带特征发射,由于Ni(Ⅱ)离子的荧光猝灭作用,配合物4没有明显的荧光产生。     

TATP-铜(II)-L-丝氨酸(L-精氨酸)配合物与DNA的相互作用

采用电子吸收光谱、荧光光谱、粘度测定和琼脂糖凝胶电泳方法研究了配合物[Cu(TATP)(L-Ser)(H2O)]·ClO4(1)和[Cu(TATP)(L-Arg)(H2O)]2ClO4·0.5H2O(2)(TATP=1,4,8,9-四氮三联苯, L-Ser=L-丝氨酸, L-Arg=L-精氨酸)与DNA之间的相互作用. 结果表明, 配合物电子吸收光谱的最大吸收峰在加入DNA后产生明显的减色效应, 配合物能极大地淬灭溴化乙啶(EB)-DNA体系的荧光, DNA的粘度随配合物浓度的增加而增大, 表明配合物对DNA有较强的插入作用, 作用力大小为配合物2>1; 另外, 凝胶电泳实验结果表明配合物在维生素C存在的条件下对pBR322 DNA具有显著的断裂作用.     

New Cu(II) complexes based on the hydroxo-bridged dinuclear [Cu(OH)2Cu] units: step-like di- and trimerizations of [Cu(OH)2Cu] units

Four new Cu(II) complexes {[Cu(4)(bpy)(4)(OH)(4)(H(2)O)(2)]}(NO(3))(2)(C(7)H(5)O(2))(2)·6H(2)O 1, {[Cu(4)(bpy)(4)(OH)(4)(H(2)O)(2)]}(NO(3))(2)(C(5)H(6)O(4))·8H(2)O 2, {[Cu(4)(bpy)(4)(OH)(4)(H(2)O)(2)]}(C(5)H(6)O(4))(2)·16H(2)O 3 and {[Cu(6)(bpy)(6)(OH)(6)(H(2)O)(2)]}(C(8)H(7)O(2))(6)·12H(2)O 4 were synthesized (bpy = 2,2'-bipyridine, H(2)(C(5)H(6)O(4)) = glutaric acid, H(C(7)H(5)O(2)) = benzoic acid, H(C(8)H(7)O(2)) = phenyl acetic acid). The building units in 1-3 are the tetranuclear [Cu(4)(bpy)(4)(H(2)O)(2)(μ(2)-OH)(2)(μ(3)-OH)(2)](4+) complex cations, and in 4 the hexanuclear [Cu(6)(bpy)(6)(H(2)O)(2)(μ(2)-OH)(2)(μ(3)-OH)(4)](6+) complex cations, respectively. The tetra- and hexanuclear cluster cores [Cu(4)(μ(2)-OH)(2)(μ(3)-OH)(2)] and [Cu(6)(μ(2)-OH)(2)(μ(3)-OH)(4)] in the complex cations could be viewed as from step-like di- and trimerization of the well-known hydroxo-bridged dinuclear [Cu(2)(μ(2)-OH)(2)] entities via the out-of-plane Cu-O(H) bonds. The complex cations are supramolecularly assembled into (4,4) topological networks via intercationic ππ stacking interactions. The counteranions and lattice H(2)O molecules are sandwiched between the 2D cationic networks to form hydrogen-bonded networks in 1-3, while the phenyl acetate anions and the lattice H(2)O molecules generate 3D hydrogen-bonded anionic framework to interpenetrate with the (4,4) topological cationic networks with the hexanuclear complex cations in the channels. The ferromagnetic coupling between Cu(II) ions in the [Cu(4)(μ(2)-OH)(2)(μ(3)-OH)(2)] cores of 1-3 is significantly stronger via equatorial-equatorial OH(-) bridges than via equatorial-apical ones. The outer and the central [Cu(2)(OH)(2)] unit within the [Cu(6)(μ(2)-OH)(2)(μ(3)-OH)(4)] cluster cores in 4 exhibit weak ferromagnetic and antiferromagnetic interactions, respectively. Results about i.r. spectra, thermal and elemental analyses are presented.     

Hydrothermal Synthesis, Crystal Structure and Magnetic Property of a Novel Pentanuclear Copper(Ⅱ) Complex: [Cu5(SIP)2(HSIP)2(H2O)18](H2O)5

The pentanuclear complex, [Cu5(SIP)2(HSIP)2(H2O)18](H2O)5 (H3SIP=5-sulfoi-sophthalic acid), has been synthesized by the hydrothermal reaction of CuCl2 with NaH2SIP at 160 ℃, and characterized by single-crystal X-ray diffraction and IR spectrum. The crystal of the complex crystallizes in a trielinic system, space group P1, with a = 7.0018(5), b = 11.9725(8), c = 19.0424(13) A, α = 78.8540(10), β = 85.1710(10),γ = 83.6080(10)~, V = 1553.24(19) A3, Z = 1, C32H60O51S4Cu5, Mr= 1706.74, Dc= 1.825 g/cm3,μ = 1.937 mm-1, F(000) = 869, the final R = 0.0709 and wR = 0.1503 for 4235 observed reflections with I > 2σ(I). The five Cu2+ ions are connected by two symmetry-related tridentate SIP3- ligands and charge-balanced by two monodentate HSIP2- ligands, giving a discrete pentanuclear structure. The pentanuclear copper molecules are linked by hydrogen bonds to form a three-dimensional supramolecular structure. The temperature-dependent magnetic susceptibility data revealed weak ferromagnetic magnetic interactions between the Cu2+ ions.     

原位羟基化2,2′-联吡啶类配体及其新颖的铜(Ⅰ)和混价铜(I,Ⅱ)超分子构筑的合成

本文利用水热法合成了两个新型一价铜配合物[Cu2(ophen)2]·H2O的类同质多晶结构(1a和1β)和一个混合价的铜配合物[Cu2(obpy)2(NO3)·H2O(2).晶体结构分析表明:1a显现出于无水的类似物[Cu2(ophen)2]相同的堆积方式,1β则形成出新奇的空间堆积.混合价化合物2是完全离域的,通过氢键集聚体[(H2O)2(NO3-)2]将两个[Cu2(obpy)2]+单元连接起来形成哑铃状的四核结构.     

Two novel heterometallic Cu(II)-Sr(II) coordination polymers based on 3,5-pyrazoledicarboxylic acid: synthesis, crystal structures and magnetic properties

The syntheses, crystal structures and magnetic properties are described for two novel 2D heterometallic Cu(II)-Sr(II) coordination polymers {Sr(H(2)O)(6)[(Im)(4)Cu(4)(pdc)(4)Sr(H(2)O)(4)]·6H(2)O}(n) (1) and [Cu(2)(H(2)O)(2)(pdc)(2)Sr(H(2)O)(3)](n) (2) (H(3)pdc = 3,5-pyrazoledicarboxylic acid; Im = imidazole). The 1 : 1 : 1 : 5 reaction of SrCl(2)·6H(2)O, Cu(NO(3))(2)·3H(2)O, H(3)pdc and imidazole in H(2)O-EtOH at 120 °C under autogenous pressure gave 1. Complex 2 was obtained from the 1 : 1 : 1 H(3)pdc/Sr(OH)(2)·8H(2)O/Cu(NO(3))(2)·3H(2)O reaction mixture in H(2)O-EtOH under solvothermal conditions. Complex 1 can be described as a 2D grid-shaped network with the four Cu(II) ions in a saddle-like conformation. In complex 2, Sr(II) ions link metalloligands [Cu(2)(pdc)(2)(H(2)O)(2)](2-) to generate a 2D layer framework. Variable-temperature solid-state dc magnetic susceptibility studies have been performed in the temperature range 2.0-300 K for complexes 1 and 2. Antiferromagnetic Cu(II)···Cu(II) exchange interactions were found for both 1 and 2.     

Self assembled tetranuclear Cu4(II), Ni4(II) [2 × 2] square grids and a dicopper(II) complex of heterocycle based polytopic ligands - Magnetic studies

The ditopic ligand PyPzOAP (N-[(Z)-amino(pyridin-2-yl)methylidene]-5-methyl-1-(pyridin-2-yl)-1H-pyrazole-3-carbohydrazonic acid) and the polytopic ligand 2-PzCAP (N'(3),N'(5)-bis[(1E)-1-(pyridin-2-yl)ethylidene]-1H-pyrazole-3,5-dicarbohydrazide) were synthesized in situ by condensation of methyl imino picolinate with 5-methyl-1-(2-pyridyl) pyrazole-3-carbohydrazide and 2-acetyl pyridine with pyrazole-3,5-dicarbohydrazide respectively. The ligands PyPzOAP and PzOAP (reported earlier, Dalton Trans., 2007, 1229) self-assemble to form homoleptic [2 × 2] tetranuclear M(4) (M = Cu(II) and Ni(II)) square grids structures [Cu(4)(PyPzOAP)(4)](NO(3))(4) (1), [Cu(4)(PzOAP)(4)](ClO(4))(4) (2) and [Ni(4)(PyPzOAP)(4)](NO(3))(4)·8H(2)O·2CH(3)CN (3). While the ligand 2-PzCAP forms a dicopper(II) complex [Cu(2)(2-PzCAP)(OH)(NO(3))(H(2)O)](NO(3))·2H(2)O (4). The complex 1 is a perfect square grid (a = 4.201 ?), whereas, 2 and 3 are almost square grids. All these compounds have been characterized by X-ray structural analyses and variable temperature magnetic susceptibility measurements. EPR studies have also been carried out for complexes 1, 2 and 4. In the Cu(4) grid (1), all the Cu(II) centers are in a distorted octahedral environment with N(4)O(2) chromophore, while, in complex 2, all four Cu(II) centers have a square pyramidal environment with N(3)O(2) chromophore. In complex 3, all four Ni(II) centers have distorted octahedral geometry with N(4)O(2) chromophore. In compound 4, the Cu(II) centers are in square pyramidal environment with N(3)O(2) chromophore. The magnetic properties of compounds 1 and 2 show the presence of intramolecular ferromagnetic exchange interaction (J = 5.88 cm(-1) for 1 and 4.78 cm(-1) for 2). The complex 3 shows weak intramolecular antiferromagnetic interaction (J = -4.02 cm(-1)). While, complex 4, shows strong antiferromagnetic behavior (J = -443 cm(-1)).     

Hydrothermal Synthesis, Crystal Structure and Magnetic Property of a Novel Pentanuclear Copper(II) Complex:[Cu_5(SIP)_2(HSIP)_2(H_2O)_(18)](H_2O)_5

The pentanuclear complex, Cu5(SIP)2(HSIP)2(H2O)18(H2O)5(H3SIP = 5-sulfoi-sophthalic acid), has been synthesized by the hydrothermal reaction of CuCl2 with NaH2SIP at 160 ℃, and characterized by single-crystal X-ray diffraction and IR spectrum.The crystal of the complex crystallizes in a triclinic system, space group P1-, with a = 7.0018(5), b = 11.9725(8), c = 19.0424(13) , α = 78.8540(10), β = 85.1710(10), γ = 83.6080(10)o, V = 1553.24(19) 3, Z = 1, C32H60O51S4Cu5, Mr = 1706.74, Dc = 1.825 g/cm3, μ = 1.937 mm-1, F(000) = 869, the final R = 0.0709 and wR = 0.1503 for 4235 observed reflections with I > 2σ(I).The five Cu2+ ions are connected by two symmetry-related tridentate SIP3-ligands and charge-balanced by two monodentate HSIP2-ligands, giving a discrete pentanuclear structure.The pentanuclear copper molecules are linked by hydrogen bonds to form a three-dimensional supramolecular structure.The temperature-dependent magnetic susceptibility data revealed weak ferromagnetic magnetic interactions between the Cu2+ ions.     

Ferroelectricity induced by ordering of twisting motion in a molecular rotor

A novel mononuclear metal-organic compound, [Cu(Hdabco)(H(2)O)Cl(3)] (1, dabco = 1,4-diazabicyclo[2.2.2]octane) in which the Cu(II) cation adopts a slightly distorted bipyramidal geometry where the three Cl anions constitute the equatorial plane and the Hdabco cation and H(2)O molecule occupy the two axial positions, was synthesized. Its paraelectric-to-ferroelectric phase transition at 235 K (T(c)) and dynamic behaviors were characterized by single crystal X-ray diffraction analysis, thermal analysis, dielectric and ferroelectric measurements, second harmonic generation experiments, and solid-state nuclear magnetic resonance measurements. Compound 1 behaves as a molecular rotor above room temperature in which the (Hdabco) part rotates around the N···N axis as a rotator and the [Cu(H(2)O)Cl(3)] part acts as a stator. In the temperature range 235-301 K, a twisting motion of the rotator is confirmed. Below the T(c), the motions of the rotor are frozen and the molecules become ordered, corresponding to a ferroelectric phase. Origin of the ferroelectricity was ascribed to relative movements of the anions and cations from the equilibrium position, which is induced by the order-disorder transformation of the twisting motion of the molecule between the ferroelectric and paraelectric phases. Study of the deuterated analogue [Cu(Ddabco)(D(2)O)Cl(3)] (2) excludes the possibility of proton ordering as the origin of the ferroelectricity in 1.     

Microwave-assisted construction of ferromagnetic coordination polymers of [W(V)(CN)8]3- with Cu(II)-pyrazole synthons

The microwave-mediated self-assembly of [W(V)(CN)(8)](3-) with Cu(II) in the presence of pyrazole ligand resulted in the formation of three novel assemblies: Cu(II)(2)(Hpyr)(5)(H(2)O)[W(V)(CN)(8)](NO(3))·H(2)O (1), {Cu(II)(5)(Hpyr)(18)[W(V)(CN)(8)](4)}·[Cu(II)(Hpyr)(4)(H(2)O)(2)]·9H(2)O (2), and Cu(II)(4)(Hpyr)(10)(H(2)O)[W(V)(CN)(8)](2)(HCOO)(2)·4.5H(2)O (3) (Hpyr =1H-pyrazole). Single-crystal X-ray structure of 1 consists of cyanido-bridged 1-D chains of vertex-sharing squares topology. The structure of 2 reveals 2-D hybrid inorganic layer topology with large coordination spaces occupied by {Cu(Hpyr)(2)(H(2)O)(4)}(2+) ions. Compound 3 contains two types of cyanido-bridged 1-D chains of vertex-sharing squares linked together by formate ions in two directions forming hybrid inorganic-organic 3-D framework (I(1)O(2)). The magnetic measurements for 1-3 reveal a weak ferromagnetic coupling through Cu(II)-NC-W(V) bridges.     

Pyrophosphate-mediated magnetic interactions in Cu(II) coordination complexes

The reaction in water of Cu(NO(3))(2)·2.5H(2)O with 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen), or 1,10-phenanthroline-5-amine (phenam), and sodium pyrophosphate (Na(4)P(2)O(7)), at various pHs, afforded three new copper(II)-pyrophosphate complexes, namely, {[Cu(bipy)(cis-H(2)P(2)O(7))](2)}·3H(2)O (1a), {[Cu(phen)(H(2)O)](4)(HP(2)O(7))(2)}(ClO(4))(2)·4H(2)O (2), and {[Cu(2)(phenam)(2)(P(2)O(7))](2)·25H(2)O}(n) (3). A solvent free crystalline phase of 1a was also isolated with formula {[Cu(bipy)(trans-H(2)P(2)O(7))](2)} (1b), which can be regarded as a pseudo-polymorph of 1a. Single crystal X-ray analyses revealed these compounds to have uncommon molecular architectures, with 3 being an unprecedented pyrophosphate-containing two-dimensional (2D) polymer. Compounds 1a/1b and 2 are discrete di- and tetra-nuclear complexes, respectively. The cationic {[Cu(phen)(H(2)O)](4)(HP(2)O(7))(2)}(2+) unit in 2 presents a unique quasi-flat structure, held together by solely in-plane pyrophosphate bridging modes (short O(eq)-P-O(eq) and long O(eq)-P-O-P-O(eq) pathways), a coordination arrangement also not previously reported. A different tetranuclear copper(II)-pyrophosphate arrangement is found in 3, with two classically bridged dimers (O(eq)-P-O(eq) pathway) joined together by auxiliary equatorial-axial μ-O pyrophosphate bridges. Here, the bidimensionality is reached through bridging phenam ligands, which provide further inter-"tetramer" metal-metal connections [(N,N')(eq)-(N')(ax) pathway], leading to the formation of an expanded covalent network based on the [Cu(2)(phenam)(2)(P(2)O(7))](2) moiety. Variable-temperature magnetic susceptibility measurements on polycrystalline samples of 2 and 3 revealed net antiferromagnetic coupling between metal centers with J(2a) = -7.9(2) cm(-1), J(2b) = -46.9(3) cm(-1), J(2c) = 0 cm(-1) in 2 (H = -J(2a)[S(Cu(1))·S(Cu(2)) + S(Cu(1a))·S(Cu(2a))] - J(2b)[S(Cu(1))·S(Cu(2a)) + S(Cu(1a))·S(Cu(2))] - J(2c)S(Cu(2))·S(Cu(2a))), and J(3a) = -87.9(2) cm(-1), J(3b) = -5(1) cm(-1) and J(3c) = +5(3) cm(-1) in 3 (H = -J(3a)[S(Cu(1))·S(Cu(2)) + S(Cu(1a))·S(Cu(2a))] - J(3b)[S(Cu(1))·S(Cu(2a)) + S(Cu(1a))·S(Cu(2))] - J(3c)S(Cu(2))·S(Cu(2a))). For 1a, a net ferromagnetic coupling is observed with J(1a) = +0.86(1) cm(-1) (H = -J S(A)·S(B) + S(A)·D· S(B) + βH (g(A)S(A) + g(B)S(B)). This is the first example of ferromagnetic coupling in pyrophosphate-complexes reported to date. A structure-function correlation study focusing on magnetic exchange across the observed diverse pyrophosphate-bridges is described with density functional theory (DFT) calculations included to support the stated observations.     

Syntheses,Crystal Structures and Properties of Co（Ⅱ） and Cu（Ⅱ） Complexes with 5-Nitro-1,2,3-benzenetricarboxylic Acid

Two new coordination polymers,{[Co(O2N-Hbtb)(phen)(H2O)3]·2H2O}n 1 and {[Cu3(O2N-btb)2(bipy)2(H2O)4]·4H2O}n 2(O2N-H3btb=5-nitro-1,2,3-benzenetricarboxylic acid,phen=1,10-phenanthroline,bipy=2,2'-bipyridine),were prepared through hydrothermal reactions of Co(Ⅱ) or Cu(Ⅱ) salt with O2N-H3btb in the presence of different auxiliary N-donor ligands.Their crystal structures were determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis and IR spectroscopy.In the two complexes,O2N-H3btb ligand acts as monodentate and bis-monodentate modes,respectively.Complex 1 displays a two-dimensional layered structure through the inter-and intramolecular hydrogen bonding interactions while complex 2 has an O2N-btb bridged one-dimensional chain which is extended into a three-dimensional network by hydrogen bonding interactions.The magnetic properties of complex 2 are investigated over the temperature range of 2～300 K and ferromagnetic interactions are observed.