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1.
本文合成了四个新型双核配合物、[Cu(samen)Fe(L)Cl]和[Cu(sampn)Fe(L)Cl]。经元素分析、IR, 电导、磁性测量等手段推定配合物具有酚氧桥结构, Cu(II)及Fe(III)的配位环境分别为平面四方及四角锥的构型, Fe(III)离子的自旋态S=3/2。测定了配合物[Cu(samen)Fe(L)Cl]的变温磁化率(4-300K), 参数J和θ值表明两个双核配合物中金属离子之间有中等程度的反铁磁性超交换作用和双核单元之间有弱的分子间相互作用。  相似文献   

2.
本文合成了两个新型双核配合物, [Cu(Samen)Co(L)2]和[Cu(Sampn)Co(L)2], Samen^4^-表示N,N'-双水杨酰代乙二胺根阴离子,Sampn^4^-表示N,N'-1,2-双水杨酰代丙二胺根阴离子, L表示5-硝基-1,10-菲咯啉(NO2-Phen)。经元素分析, IR和电子光谱等推定配合物具有酚氧桥结构,Cu(II)及Co(II)的配位环境分别为平面四方及畸变八面体构型。测定了配合物(4-300K)的变温磁化率, 并用最小二乘法和自旋Hamiltonian算符,H=2JS1.S2-DSzl导出的磁方程拟合, 求得交换参数为J=-4.39(Samen)和-3.59cm^-^1(Sampn), 表明两个Cu(II)-Co(II)双核配合物中有弱的反铁磁性超交换相互作用。  相似文献   

3.
对苯二甲酸根桥联的双核铬(Ⅲ)配合物的合成与磁性   总被引:1,自引:0,他引:1  
以对苯二甲酸根(TPHA)为桥联配体.分别端接4.4'-二甲基-2.2'-联吡啶(Me 2bpy),2.9-二甲基-1.10-邻菲哕啉(Me2phen)和5-氯-1,10-邻菲哕啉(Cl-phen).合成了3种新的双核铬(Ⅲ)配合物[Cr2-(TPHA)(Me2bpy)4](NO3)4(1),[Cr2(TPHA)(Me2phen)4](NO3)4(2)和[Cr 2(TPHA)(Clphen)4](N)3)4(3).经元素分析、摩尔电导和磁性测定以及红外光谱和电子光谱等手段,推定这些配合物具有TPHA桥联双核铬(Ⅲ)结构,其中,每个铬(Ⅲ)离子处于畸变八面体配位环境.测定了配合物(1)的变温磁化率(4~300 K),其数值用最小二乘法和从自旋Hamiltonian算符(H=-2JS^1S^2)导出的磁方程拟合,求得交换积分为-2.98 cm-1,结果表明双核配合物中金属离子间存在弱的反铁磁自旋交换作用.  相似文献   

4.
Three new cobalt(II) binuclear complexes have been prepared and characterized, namely [Co2(TCPHTA)(L)4](ClO4)2 [L=1,10-phenanthroline (phen), 5-nitro-1,10-phenanthroline(NO2-phen) and 2, 2-bipyridyl (bipy), respectively], where TCPHTA is the tetrachlorophthalate dianion. Based on i.r. spectra, elemental analyses and conductivity measurements, tetrachlorophthalato-bridged structures consisting of two cobalt(II) ions in which each cobalt(II) ion has a distorted octahedral environment are proposed for these complexes. The temperature dependence of the magnetic susceptibility for [Co2(TCPHTA)(L)4](ClO4)2·nH2O (L=phen, NO2-phen and bipy) has been measured over the 77–300 K range and the observed data successfully simulated by an equation based on the spin Hamiltonian operator (H=–2JS1S2), giving the exchange integral J=–2.92, –3.45, –4.03 cm–1, respectively. This result indicates the presence of a weak antiferromagnetic spin exchange interaction between the metal ions.  相似文献   

5.
Four new heterotrinuclear complexes have been synthesized and characterized, namely {[Ni(L)2]2[Cu(opba)]}(ClO4)2, where opba denotes o-phenylenebis(oxamato) and L stands for 1,10-phenanthroline(phen) (1), 5-nitro-1,10-phenanthroline(NO2-phen) (2), 2,2'-bipyridyl(bpy) (3) and 4,4'-dimethyl-2,2'-bipyridyl(Me2bpy) (4). The temperature dependence of the magnetic susceptibility of {[Ni(phen)2]2[Cu(opba)]}(ClO4)2.3H2O has been studied in the 4-300 K range, giving the exchange integral J=-109 cm-1. The MT vs. T plot exhibits a minimum at about 100 K, characteristic of this kind of coupled polymetallic complex with an irregular spin-state structure.  相似文献   

6.
合成了 7种草酸根桥联的 Cu 2 Fe 、Ni 2 Fe 、Co 2 Fe 异三核配合物 [M2 Fe(C2 O4) 3Lx](Cl O4) ,(M=Cu,L=bpy,Me2 phen,NO2 phen,x=2 ;M=Ni,Co,L=bpy,Me2 phen,x=4 ) .经元素分析、摩尔电导和磁性的测定以及红外光谱和电子光谱等方法对这些配合物进行了表征 ,确定了配合物的组成和结构 .初步生物活性试验表明形成异三核配合物后其杀菌活性明显提高  相似文献   

7.
合成了7种草酸根桥联的CuⅡ2FeⅢ、NiⅡ2FeⅢ、CoⅡ2FeⅢ异三核配合物[M2Fe(C2O4)3Lx](ClO4),(M=Cu,L=bpy,Me2phen,NO2phen,x=2;M=Ni,Co,L=bpy,Me2phen,x=4).经元素分析、摩尔电导和磁性的测定以及红外光谱和电子光谱等方法对这些配合物进行了表征,确定了配合物的组成和结构.初步生物活性试验表明形成异三核配合物后其杀菌活性明显提高.  相似文献   

8.
廖代正  林兵  王耕霖 《化学学报》1992,50(3):269-273
合成和表征了两种新的异双核配合物[Cu(oxap)Mn(L)~2](ClO~4)~2, oxap表示N,N'-双(2-氨基丙基)草酰胺根阴离子, L表示1,10-邻菲咯啉(phen)和5-硝基-1,10-邻菲咯啉(NO~2-phen)。测定了配合物的变温磁化率(4.2-300K), 并用最小二乘法和从自旋Hamiltonian算符, ^^H=-2J^^S~1.^^S~2-D^^S~Z~1导出的磁方程拟合。求得交换积分为J=-74.72cm^-^1(phen)和J=-76.39cm^-^1(No~2-phen), 表明两个Cu(II)-Mn(II)双核配合物中有中等强度的反铁磁超交换作用。  相似文献   

9.
合成了3种新型配合物[Cu(samen)Mn(NO_(2-)Phen)_2](1)、[Cu(sampn)Mn(NO_(2-)Phen)_2](2)和[Cu(samen)CO(terp)](3)(samen~(4-)、sampn~(4-)、NO_(2-)Phen和terp分别表示N,N′-乙二水杨酰胺根阴离子、N,N′-1,2-丙二水杨酰胺根阴离子、5-硝基-1,10-菲绕啉和联三吡啶),测得配合物的变温磁化率,求出交换积分,J分别为-63cm~(-1)(1)、—65cm~(-1)(2)和—7.68cm~(-1)(3),表明金属离子间有反铁磁超交换作用。  相似文献   

10.
合成和表征了三种新的异三核配合物, {[Gd(L)2]2[Cu(pba)]}(ClO4)4,其中pba为1,3-亚丙基双(草胺酸根)和L表示1,10-菲咯啉(phen),5-硝基-1,10-菲咯啉(NO2-phen)或2,2'-联吡啶(bpy)。基于{[Gd(phen)2(ClO4)]2[Cu(pba)]}(ClO4)2.2H2O的变温磁化率测量(4.1~300K),求出交换积分J=3.576cm^-^1。表明在铜(Ⅱ)和钆(Ⅲ)离子间存在铁磁性偶合。  相似文献   

11.
Two novel heterobimetallic complexes of formula [Cr(bpy)(ox)(2)Co(Me(2)phen)(H(2)O)(2)][Cr(bpy)(ox)(2)]·4H(2)O (1) and [Cr(phen)(ox)(2)Mn(phen)(H(2)O)(2)][Cr(phen)(ox)(2)]·H(2)O (2) (bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline, and Me(2)phen = 2,9-dimethyl-1,10-phenanthroline) have been obtained through the "complex-as-ligand/complex-as-metal" strategy by using Ph(4)P[CrL(ox)(2)]·H(2)O (L = bpy and phen) and [ML'(H(2)O)(4)](NO(3))(2) (M = Co and Mn; L' = phen and Me(2)phen) as precursors. The X-ray crystal structures of 1 and 2 consist of bis(oxalato)chromate(III) mononuclear anions, [Cr(III)L(ox)(2)](-), and oxalato-bridged chromium(III)-cobalt(II) and chromium(III)-manganese(II) dinuclear cations, [Cr(III)L(ox)(μ-ox)M(II)L'(H(2)O)(2)](+)[M = Co, L = bpy, and L' = Me(2)phen (1); M = Mn and L = L' = phen (2)]. These oxalato-bridged Cr(III)M(II) dinuclear cationic entities of 1 and 2 result from the coordination of a [Cr(III)L(ox)(2)](-) unit through one of its two oxalato groups toward a [M(II)L'(H(2)O)(2)](2+) moiety with either a trans- (M = Co) or a cis-diaqua (M = Mn) configuration. The two distinct Cr(III) ions in 1 and 2 adopt a similar trigonally compressed octahedral geometry, while the high-spin M(II) ions exhibit an axially (M = Co) or trigonally compressed (M = Mn) octahedral geometry in 1 and 2, respectively. Variable temperature (2.0-300 K) magnetic susceptibility and variable-field (0-5.0 T) magnetization measurements for 1 and 2 reveal the presence of weak intramolecular ferromagnetic interactions between the Cr(III) (S(Cr) = 3/2) ion and the high-spin Co(II) (S(Co) = 3/2) or Mn(II) (S(Mn) = 5/2) ions across the oxalato bridge within the Cr(III)M(II) dinuclear cationic entities (M = Co and Mn) [J = +2.2 (1) and +1.2 cm(-1) (2); H = -JS(Cr)·S(M)]. Density functional electronic structure calculations for 1 and 2 support the occurrence of S = 3 Cr(III)Co(II) and S = 4 Cr(III)Mn(II) ground spin states, respectively. A simple molecular orbital analysis of the electron exchange mechanism suggests a subtle competition between individual ferro- and antiferromagnetic contributions through the σ- and/or π-type pathways of the oxalato bridge, mainly involving the d(yz)(Cr)/d(xy)(M), d(xz)(Cr)/d(xy)(M), d(x(2)-y(2))(Cr)/d(xy)(M), d(yz)(Cr)/d(xz)(M), and d(xz)(Cr)/d(yz)(M) pairs of orthogonal magnetic orbitals and the d(x(2)-y(2))(Cr)/d(x(2)-y(2))(M), d(xz)(Cr)/d(xz)(M), and d(yz)(Cr)/d(yz)(M) pairs of nonorthogonal magnetic orbitals, which would be ultimately responsible for the relative magnitude of the overall ferromagnetic coupling in 1 and 2.  相似文献   

12.
Tetranuclear copper(II) complexes containing alpha-D-glucose-1-phosphate (alpha-D-Glc-1P), [Cu4(mu-OH){mu-(alpha-D-Glc-1P)}2(bpy)4(H2O)2]X3 [X = NO3 (1a), Cl (1b), Br (1c)], and [Cu4(mu-OH){mu-(alpha-D-Glc-1P)}2(phen)4(H2O)2](NO3)3 (2) were prepared by reacting the copper(II) salt with Na2[alpha-D-Glc-1P] in the presence of diimine ancillary ligands, and the structure of 2 was characterized by X-ray crystallography to comprise four {Cu(phen)}2+ fragments connected by the two sugar phosphate dianions in 1,3-O,O' and 1,1-O mu4-bridging fashion as well as a mu-hydroxo anion. The crystal structure of 2 involves two chemically independent complex cations in which the C2 enantiomeric structure for the trapezoidal tetracopper(II) framework is switched according to the orientation of the alpha-D-glucopyranosyl moieties. Temperature-dependent magnetic susceptibility data of 1a indicated that antiferromagnetic spin coupling is operative between the two metal ions joined by the hydroxo bridge (J = -52 cm(-1)) while antiferromagnetic interaction through the Cu-O-Cu sugar phosphate bridges is weak (J = -13 cm(-1)). Complex 1a readily reacted with carboxylic acids to afford the tetranuclear copper(II) complexes, [Cu4{mu-(alpha-D-Glc-1P)}2(mu-CA)2(bpy)4](NO3)2 [CA = CH3COO (3), o-C6H4(COO)(COOH) (4)]. Reactions with m-phenylenediacetic acid [m-C6H4(CH2COOH)2] also gave the discrete tetracopper(II) cationic complex [Cu4{mu-(alpha-D-Glc-1P)}2(mu-m-C6H4(CH2COO)(CH2COOH))2(bpy)4](NO3)2 (5a) as well as the cluster polymer formulated as {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-m-C6H4(CH2COO)2)(bpy)4](NO3)2}n (5b). The tetracopper structure of 1a is converted into a symmetrical rectangular core in complexes 3, 4, and 5b, where the hydroxo bridge is dissociated and, instead, two carboxylate anions bridge another pair of Cu(II) ions in a 1,1-O monodentate fashion. The similar reactions were applied to incorporate sugar acids onto the tetranuclear copper(II) centers. Reactions of 1a with delta-D-gluconolactone, D-glucuronic acid, or D-glucaric acid in dimethylformamide resulted in the formation of discrete tetracopper complexes with sugar acids, [Cu4{mu-(alpha-D-Glc-1P)}2(mu-SA)2(bpy)4](NO3)2 [SA = D-gluconate (6), D-glucuronate (7), D-glucarateH (8a)]. The structures of 6 and 7 were determined by X-ray crystallography to be almost identical with that of 3 with additional chelating coordination of the C-2 hydroxyl group of D-gluconate moieties (6) or the C-5 cyclic O atom of D-glucuronate units (7). Those with D-glucaric acid and D-lactobionic acid afforded chiral one-dimensional polymers, {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-D-glucarate)(bpy)4](NO3)2}n (8b) and {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-D-lactobionate)(bpy)4(H2O)2](NO3)3}n (9), respectively, in which the D-Glc-1P-bridged tetracopper(II) units are connected by sugar acid moieties through the C-1 and C-6 carboxylate O atoms in 8b and the C-1 carboxylate and C-6 alkoxy O atoms of the gluconate chain in 9. When complex 7 containing d-glucuronate moieties was heated in water, the mononuclear copper(II) complex with 2-dihydroxy malonate, [Cu(mu-O2CC(OH)2CO2)(bpy)] (10), and the dicopper(II) complex with oxalate, [Cu2(mu-C2O4)(bpy)2(H2O)2](NO3)2 (11), were obtained as a result of oxidative degradation of the carbohydrates through C-C bond cleavage reactions.  相似文献   

13.
Yu SY  Huang HP  Li SH  Jiao Q  Li YZ  Wu B  Sei Y  Yamaguchi K  Pan YJ  Ma HW 《Inorganic chemistry》2005,44(25):9471-9488
A series of nanosized cavity-containing bipyrazolate-bridged metallomacrocycles with dimetal centers, namely, {[(bpy)M]8L4}(NO3)8 [L=3,3',5,5'-tetramethyl-4,4'-bipyrazolyl, Pd, Pt; 1,4-bis-4'-(3',5'-dimethyl)-pyrazolylbenzene), Pd; and 1,4-bis-4'-(3',5'-dimethyl)-pyrazolylbiphenyl, Pd], {[(phen)M]8L4}(NO3)8 [L=3,3',5,5'-tetramethyl-4,4'-bipyrazolyl, Pd, Pt; 1,4-bis-4'-(3',5'-dimethyl)-pyrazolylbenzene, Pd; and 1,4-bis-4'-(3',5'-dimethyl)-pyrazolylbiphenyl, Pd], {[(bpy)Pd]6L3}(NO3)6 [L=1,4-bis-4'-(3',5'-dimethyl)-pyrazolylbenzene,], {[(phen)Pd]6L3}(NO3)6 [L=1,4-bis-4'-(3',5'-dimethyl)-pyrazolylbenzene,], {[(bpy)Pd]4L2}(NO3)4 [L=1,3-bis-4'-(3',5'-dimethyl)-pyrazolylbenzene, and 1,2-bis-4'-(3',5'-dimethyl)-pyrazolylbenzene,], and {[(phen)Pd]4L2}(NO3)4 [L=1,3-bis-4'-(3',5'-dimethyl)-pyrazolylbenzene, and 1,2-bis-4'-(3',5'-dimethyl)-pyrazolylbenzene,] (where bpy=2,2'-bipyridine and phen=1,10-phenanthroline) have been synthesized through a directed self-assembly approach that involves spontaneous deprotonation of the 1H-bipyrazolyl ligands in aqueous solution. These complexes, with weak Pd(II)...Pd(II) or Pt(II)...Pt(II) interactions, have been characterized by elemental analysis, 1H and 13C NMR, cold-spray ionization or electrospray ionization mass spectrometry, UV-visible spectroscopy, and luminescence spectroscopy. Complexes and have also been characterized by single-crystal X-ray diffraction analysis.  相似文献   

14.
Reactions of CuX2.nH2O with the biscarboxylate ligand XDK (H2XDK = m-xylenediamine bis(Kemp's triacid imide)) in the presence of N-donor auxiliary ligands yielded a series of dicopper(II) complexes, [Cu2(mu-OH)(XDK)(L)2]X (L = N,N,N',N'-tetramethylethylenediamine (tetmen), X = NO3 (1a), Cl (1b); L = N,N,N'-trimethylethylenediamine (tmen), X = NO3 (2a), Cl (2b); L =2,2'-bipyridine (bpy), X = NO3 (3); L = 1,10-phenanthroline (phen), X = NO3 (4); L = 4,4'-dimethyl-2,2'-bipyridine (Me2bpy), X = NO3 (5); L = 4-methyl-1,10-phenanthroline (Mephen), X = NO3 (6)). Complexes 1-6 were characterized by X-ray crystallography (Cu...Cu = 3.1624(6)-3.2910(4) A), and the electrochemical and magnetic properties were also examined. Complexes 3 and 4 readily reacted with diphenyl phosphoric acid (HDPP) or bis(4-nitrophenyl) phosphoric acid (HBNPP) to give [Cu2(mu-phosphate)(XDK)(L)2]NO3 (L = bpy, phosphate = DPP (11); L = phen, phosphate = DPP (12), BNPP (13)), where the phsophate diester bridges the two copper ions in a mu-1,3-O,O' bidentate fashion (Cu...Cu = 4.268(3)-4.315(1) A). Complexes 4 and 6 with phen and Mephen have proven to be good precursors to accommodate a series of sugar monophosphate esters (Sugar-P) onto the biscarboxylate-bridged dicopper centers, yielding [Cu2(mu-Sugar-P)(XDK)(L)2] (Sugar-P = alpha-D-Glc-1-P (23a and b), D-Glc-6-P (24a and b), D-Man-6-P (25a), D-Fru-6-P (26a and b); L = phen (a), Mephen (b)) and [Cu2(mu-Gly-n-P)(XDK)(Mephen)2] (Gly-n-P = glycerol n-phosphate; n = 2 (21), 3 (22)), where Glc, Man, and Fru are glucose, mannose, and fructose, respectively. The structure of [Cu2(mu-MNPP)(XDK)(phen)2(CH3OH)] (20) was characterized as a reference compound (H2MNPP = 4-nitrophenyl phosphoric acid). Complexes 4 and 6 also reacted with d-fructose 1,6-bisphosphate (D-Fru-1,6-P2) to afford the tetranuclear copper(II) complexes formulated as [Cu4(mu-D-Fru-1,6-P2)(XDK)2(L)4] (L = phen (27a), Mephen (27b)). The detailed structure of 27a was determined by X-ray crystallography to involve two different tetranuclear complexes with alpha- and beta-anomers of D-Fru-1,6-P2, [Cu4(mu-alpha-D-Fru-1,6-P2)(XDK)2(phen)4] and [Cu4(mu-beta-D-Fru-1,6-P2)(XDK)2(phen)4], in which the D-Fru-1,6-P2 tetravalent anion bridges the two [Cu2(XDK)(phen)2]2+ units through the C1 and C6 phosphate groups in a mu-1,3-O,O' bidentate fashion (Cu...Cu = 4.042(2)-4.100(2) A). Notably, the structure with alpha-D-Fru-1,6-P2 demonstrated the presence of a strong hydrogen bond between the C2 hydroxyl group and the C1 phosphate oxygen atom, which may support the previously proposed catalytic mechanism in the active site of fructose-1,6-bisphosphatase.  相似文献   

15.
Four new binuclear Mn(III) complexes with carboxylate bridges have been synthesized: [[Mn(nn)(H(2)O)](2)(mu-ClCH(2)COO)(2)(mu-O)](ClO(4))(2) with nn = bpy (1) or phen (2) and [[Mn(bpy)(H(2)O)](2)(mu-RCOO)(2)(mu-O)](NO(3))(2) with RCOO = ClCH(2)COO (3) or CH(3)COO (4). The characterization by X-ray diffraction (1 and 3) and X-ray absorption spectroscopy (XAS) (1-4) displays the relevance of this spectroscopy to the elucidation of the structural environment of the manganese ions in this kind of compound. Magnetic susceptibility data show an antiferromagnetic coupling for all the compounds: J = -2.89 cm(-1) (for 1), -8.16 cm(-1) (for 2), -0.68 cm(-1) (for 3), and -2.34 cm(-1) (for 4). Compounds 1 and 3 have the same cation complex [[Mn(bpy)(H(2)O)](2)(mu-ClCH(2)COO)(2)(mu-O)](2+), but, while 1 shows an antiferromagnetic coupling, for 3 the magnetic interaction between Mn(III) ions is very weak. The four compounds show catalase activity, and when the reaction stopped, Mn(II) compounds with different nuclearity could be obtained: binuclear [[Mn(phen)(2)](mu-ClCH(2)COO)(2)](ClO(4))(2), trinuclear [Mn(3)(bpy)(2)(mu-ClCH(2)COO)(6)], or mononuclear complexes without carboxylate. Two Mn(II) compounds without carboxylate have been characterized by X-ray diffraction: [Mn(NO(3))(2)(bpy)(2)][Mn(NO(3))(bpy)(2)(H(2)O)]NO(3) (5) and [Mn(bpy)(3)](ClO(4))(2).0.5 C(6)H(4)-1,2-(COOEt)(2).0.5H(2)O (8).  相似文献   

16.
本文合成了两个新的双核配合物, [Cu(sampu)Ni(L)2], sampn^4^-表示N,N'-1,2-丙二水杨酰胺阴离子, L表示2,2-联吡啶(bpy)或1,10-菲咯啉(phen),经元素分析, IR和电子光谱等方法已推定配合物具有酚氧桥结构和Cu(II)及Ni(II)的配位环境分别为平面四方及八面体构型, 配合物的变温磁化率已测(4-300K), 其数值用最小二乘法和从自旋哈密顿算符H=-2JS1S2导出的磁方程拟合, 求得交换参数为J=-1.90cm^-^1(pby)和J=1.68cm^-^1(phen), 表明两个Cu(II)-Ni(II)双核配合物中有弱的反铁磁自旋交换相互作用。  相似文献   

17.
Two heterodimetallic complexes of formulae [LCo(MeOH)Gd (NO3)3] (1) and [LCo(AcO)2Gd(NO3)2] (2) (H2L = 1,3-bis[(3-methoxysalicylidene)amino]-2,2'-dimethylpropane) have been synthesized and characterized. The structure of 1 consists of discrete dinuclear entities. The cobalt(II) ion exhibits a square-pyramidal geometry, in which the basal plane is formed by the N2O2 set of the inner Schiff base site and the apical position is occupied by the methanol oxygen atom. The gadolinium(III) ion is ten-coordinate to three bidentate nitrate groups and the four oxygen atoms of the Schiff base. The phenolate oxygen atoms act as a bridge between both metal ions. Complex 2 is also formed by isolated dinuclear species. The cobalt(III) ion shows a distorted octahedral geometry in which the equatorial plane is formed by the N2O2 set of the Schiff base, and the axial positions are occupied by two oxygen atoms from both acetate groups. The gadolinium(III) ion is ten-coordinate to two bidentate nitrate groups, two oxygen atoms of the acetate groups, and the four oxygen atoms of the Schiff base. The metal ions are bridged through both the phenolate oxygen and the acetate groups, the latter acting as mu 2 ligands. Magnetic measurements on compound 1 allowed, for the first time, a quantitative evaluation of the J(Co,Gd) ferromagnetic interaction parameter (J = 0.90 cm-1). The CoII zero-field splitting has to be taken into account to fit the experimental data at low temperature (D = 4.2 cm-1). In complex 2, the magnetically isolated gadolinium center obeys a Curie law.  相似文献   

18.
Ni ZH  Kou HZ  Zheng L  Zhao YH  Zhang LF  Wang RJ  Cui AL  Sato O 《Inorganic chemistry》2005,44(13):4728-4736
Two new cyano-bridged heterobinuclear complexes, [Mn(II)(phen)2Cl][Fe(III)(bpb)(CN)2] x 0.5CH3CH2OH x 1.5H2O (1) and [Mn(II)(phen)2Cl][Cr(III)(bpb)(CN)2] x 2H2O (2) [phen = 1,10-phenanthroline; bpb(2-) = 1,2-bis(pyridine-2-carboxamido)benzenate], and four novel azido-bridged Mn(II) dimeric complexes, [Mn2(phen)4(mu(1,1)-N3)2][M(III)(bpb)(CN)2]2 x H2O [M = Fe (3), Cr (4), Co (5)] and [Mn2(phen)4(mu(1,3)-N3)(N3)2]BPh4 x 0.5H2O (6), have been synthesized and characterized by single-crystal X-ray diffraction analysis and magnetic studies. Complexes 1 and 2 comprise [Mn(phen)2Cl]+ and [M(bpb)(CN)2]- units connected by one cyano ligand of [M(bpb)(CN)2]-. Complexes 3-5 are doubly end-on (EO) azido-bridged Mn(II) binuclear complexes with two [M(bpb)(CN)2]- molecules acting as charge-compensating anions. However, the Mn(II) ions in complex 6 are linked by a single end-to-end (EE) azido bridging ligand with one large free BPh4(-) group as the charge-balancing anion. The magnetic coupling between Mn(II) and Fe(III) or Cr(III) in complexes 1 and 2 was found to be antiferromagnetic with J(MnFe) = -2.68(3) cm(-1) and J(MnCr) = -4.55(1) cm(-1) on the basis of the Hamiltonian H = -JS(Mn)S(M) (M = Fe or Cr). The magnetic interactions between two Mn(II) ions in 3-5 are ferromagnetic in nature with the magnetic coupling constants of 1.15(3), 1.05(2), and 1.27(2) cm(-1) (H = -JS(Mn1)S(Mn2)), respectively. The single EE azido-bridged dimeric complex 6 manifests antiferromagnetic interaction with J = -2.29(4) cm(-1) (H = -JS(Mn1)S(Mn2)). Magneto-structural correlationship on the EO azido-bridged Mn(II) dimers has been investigated.  相似文献   

19.
Six new copper(II) complexes of formula [Cu(mu-cbdca)(H2O)]n (1) (cbdca = cyclobutanedicarboxylate), [Cu2(mu-cbdca)2(mu-bipy)2]n (2) (bipy = 4,4'-bipyridine), [Cu(mu-cbdca)(mu-bpe)]n (3) (bpe = 1,2-bis(4-pyridyl)ethane), [Cu(mu-cbdca)(bpy)]2 (4) (bpy = 2,2'-bipyridine), [Cu(terpy)(ClO4)]2(mu-cbdca).H2O (5) (terpy = 2,2':6',2' '-terpyridine), and [Cu(cbdca)(phen) (H2O)].2H2O (6) (phen = 1,10-phenanthroline) were obtained and structurally characterized by X-ray crystallography. Complex 1 is a two-dimensional network with a carboxylate bridging ligand in syn-anti (equatorial-equatorial) coordination mode. Complexes 2 and 3 are formed by chains through syn-anti (equatorial-apical) carboxylate bridges, linked to one another by the corresponding amine giving two-dimensional nets. Complexes 4 and 5 are dinuclear, with the copper ions linked by two oxo (from two different carboxylate) bridging ligands in 4 and with only one carboxylate showing the unusual bis-unidentate mode in complex 5. Complex 6 is mononuclear, with the carboxylate linked to copper(II) in a chelated form. Intermolecular hydrogen bonds and pi-pi stacking interactions build an extended two-dimensional network. Magnetic susceptibility measurements of complexes 1-5 in the temperature range 2-300 K show the occurrence of weak ferromagnetic coupling for 1 and 4 (J = 4.76 and 4.44 cm(-1), respectively) and very weak antiferromagnetic coupling for 2, 3, and 5 (J = -0.94, -0.67, and -1.61 cm(-1), respectively). Structural features and magnetic values are compared with those reported for the similar copper(II) malonate and phenylmalonate complexes.  相似文献   

20.
The complexes of transition metal ions with an azamacrocyclic tetradentate nitrogen donor [N4] ligand viz. 2,6,12,16,21,22-hexaaza;3,5,13,15-tetramethyltricyclo[15.3.1.1(7-11)] docosa;1(21),2,5,7,9,11(22),12,15,17,19-decaene (L) have been synthesized. All the complexes were found to have general composition M(L)X2 [where M = manganese(II), cobalt(II), nickel(II) and copper(II) and X = Cl- & NO3-]. All the complexes are characterized by the elemental analysis, molar conductance measurements, magnetic susceptibility measurements, mass, 1H NMR, IR, electronic, EPR spectral and cyclic voltammetric studies. An octahedral geometry was assigned for Mn(II), Co(II) and Ni(II) complexes and tetragonal for Cu(II) complexes. The biological actions of the ligand and complexes have been screened in vitro against many bacteria and pathogenic fungi to study their comparative capacity to inhibit the growth.  相似文献   

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