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1.
Two coordination polymers {[Co3L3(Me2NH)2]·(Me2NH)}n(1) and [CuL(bpy)]n(2)(L=2,2'-biphenyl dicarboxylate ion, bpy=4,4'-bipyridine) were obtained and characterized. Compound 1 was synthesised via solvothermal method, with the L ligands adopting syn-syn-μ211- and μ22-coordination modes and Co(II) centers being linked to form a 1D coordination chain with trinuclear Co3 cluster as sub-units. Compound 2 was synthesized at room temperature, with the L ligand chelating the Cu(II) centers to form a 1D chain, which was further linked by the auxiliary 4,4'-bpy ligand to form a 3D coordination network. The results of variable temperature susceptibility studies reveal that there were ferromagnetic and antiferromagnetic interactions between the paramagnetic metal centers in compounds 1 and 2, respectively.  相似文献   

2.
用分步合成法得到了2个结构新颖的一维之字链异三金属配位聚合物{[Cu(Me_2valpn)Dy(DMF)_2(H_2O)Fe(CN)_6]·1.5H_2O·0.5CH_3OH}n(1)和{[Cu(Me_2valpn)Tb(DMF)_2(H_2O)Fe(CN)_6]·H_2O·CH_3OH}n(2)(H_2Me_2valpn=N,N′-双(3-甲氧基-水杨醛)缩-2,2-二甲基-1,3-丙二胺)。X射线单晶衍射分析表明每个[Fe(CN)_6]3-用顺式的2个氰根分别连接2个相邻构筑单元[Cu(Me_2valpn)Ln(DMF)_2(H_2O)]_3+的Cu(Ⅱ)和Ln(Ⅲ)。除了Cu(Ⅱ)和Ln(Ⅲ)之间的双酚氧桥之外,链中还包含Fe-C≡N-Cu和Fe-C≡N-Ln两类弯曲的桥联结构。配合物1在9.5~300 K的直流变温磁化率数据符合居里-韦斯定律,韦斯常数(θ)为13.17 K,表明配合物1总体上表现铁磁相互作用。交流磁化率测试表明配合物1没有表现出缓慢磁弛豫现象。  相似文献   

3.
Two tetranuclear manganese complexes, [NaMnIIMn3III4‐O2–)(HL)3(SCN)4] ( 1 ) and [NaMnIIMn3III4‐O2–)(HL)3Cl4][NaMnIIMn3III4‐O2–)(HL)3Cl3(H2O)]ClO4 · 3.5H2O ( 2 ) were obtained from the reaction of manganese perchlorate with a quadridentate Schiff base ligand, 3‐(2‐hydroxybenzylideneamino)propane‐1, 2‐diol (H3L) derived from condensation of 2‐hydroxybenzaldehyde with 3‐amino‐1, 2‐propanediol, as well as the coligand KSCN or NaCl under basic conditions. Single‐crystal X‐ray studies reveal that those two complexes all have a mixed‐valent tetrahedral core, which contains an apical MnII ion and three basal MnIII ions situated in the [Mn34‐O2–)]7+ equilateral triangle plane. Fitting of the magnetic susceptibility data to the theoretical χmT vs. T expression, revealed that the presence of only antiferromagnetic interactions between the central metal atoms in 1 , while both antiferromagnetic and ferromagnetic interactions are present in 2 .  相似文献   

4.
Three dinuclear lanthanide complexes [Ln2(H2L)2(NO3)4] [Ln = Dy ( 1 ), Tb ( 2 ), and Gd ( 3 )] [H3L = 2‐hydroxyimino‐N′‐[(2‐hydroxy‐3‐methoxyphenyl)methylidene]‐propanohydrazone] were solvothermally synthesized by varying differently anisotropic rare earth ions. Single‐crystal structural analyses demonstrate that all the three complexes are crystallographically isostructural with two centrosymmetric LnIII ions aggregated by a pair of monodeprotonated H2L anions. Weak intramolecular antiferromagnetic interactions with different strength were mediated by a pair of phenoxo bridges due to superexchange and/or single‐ion anisotropy. Additionally, the DyIII‐based entity shows the strongest anisotropy exhibits field‐induced single‐molecule magnetic behavior with two thermally activated relaxation processes. In contrast, 3 with isotropic GdIII ion has a significant cryogenic magnetocaloric effect with the maximum entropy change of 25.7 J · kg–1 · K–1 at 2.0 K and 70.0 kOe.  相似文献   

5.
Two new Schiff base complexes, [NiL]ClO4 1 and [CuL]ClO4.0.5H2O 2, were synthesized and characterized, where L is the 1:1 condensation product of salicylaldehyde and diethylenetriamine. Their crystal structures and magnetic properties were determined and investigated. The H-bonding interactions concern just in neighbor cation and anion, do not extendin to network for both 1 and 2. The temperature dependence of the magnetic susceptibilities(2-300K) showed that 1 is diamagnetism and 2 is paramagnetism with weak antiferromagnetic exchange interactions between adjacent spin carriers, no magnetic ordering taking place in these two complexes.  相似文献   

6.
Three new gallium complexes formulated as [Ga(PDA)2][Ga(H2O)(PDA)(phen)]·4H2O(1), [Ga(PDA)2]· (H2IN)·2H2O(2) and [Ga(OH)(PDA)(H2O)]2(3)(H2PDA=pyridine-2,6-dicarboxylic acid; phen=1,10-phenanthroline; HIN=isonicotinic acid) have been synthesized under hydrothermal conditions. In the mixed-ligand system of complex 1, PDA2? and phen are connected to the central Ga3+ cation as tri- and bi-dentate ligands, respectively. In complex 2, each Ga3+ cation is six-coordinated by two PDA2? anions octahedrally. Complex 3 shows a binuclear structure, with the bond distance of Ga1-Ga2 being 0.30061(3) nm. The 3D supramolecular structures of the three complexes are constructed via hydrogen bonds and aromatic π-π packing interactions. All the three complexes exhibit intense blue emission at room temperature in the solid state, which are attributed to π*-π transition centered on the ligands.  相似文献   

7.
Two N'-(2-hydroxybenzylidene)pyridine N-oxide-carbohydrazide (H3L)-based coordination complexes with the formula [Ln2(DMF)2(OAc)2(HL)2]n (Ln = Dy for 1 and Eu for 2 ) were solvothermally synthesized. Crystal structures, thermal stabilities, magnetic and luminescent properties of the two complexes were fully investigated. Both complexes are isomorphic two-dimensional layers with centrosymmetric {Ln2} subunits extended by doubly deprotonated HL2– connectors. Complex 1 with highly anisotropic DyIII spin exhibits slightly frequency-dependent magnetic relaxations under zero dc field with an effective energy barrier of ca. 6.84 K. EuIII-based complex 2 displays only one weak fluorescent emission around 532 nm with the absence of characteristic emission of EuIII ion. These results provide helpful hints of the hydrazide Schiff-functionalized organic ligands on the function modulations of the resulting Ln complexes.  相似文献   

8.
Two heterospin complexes [Cu(NIT3Py)(cda)H2O] · H2O ( 1 ) and [Cu(NIT2Py)(cda)H2O] · H2O · CH3OH ( 2 ) with CuII ions and pyridyl‐substituted nitronyl nitroxide radicals (NITxPy = 2‐(x′‐pyridyl)‐4,4,5,5‐tetramethyl‐imidazoline‐1‐oxyl‐3‐oxide, x = 3, 2; H2cda = 4‐hydroxy‐pyridine‐2,6‐dicarboxylic acid) were synthesized and characterized structurally and magnetically. The single crystal structures show that the two complexes are both two‐spin complexes, in which the different radicals make the two complexes have different hydrogen bonding interactions to form 2D and 1D supramolecular network for complexes 1 and 2 , respectively. The magnetic measurements indicate that complexes 1 and 2 both exhibit antiferromagnetic interactions between CuII and radicals.  相似文献   

9.
The cis-doubly N-confused porphyrin (cis-N2CP, 1) and its Cu(III) and Ag(III) complexes (1–Cu, 1–Ag) form 1-D zigzag infinite chains through hydrogen-bonding interactions between the peripheral core nitrogens (N and NH) in the solid state. Each columnar structure consists of porphyrin rings with the same chirality.  相似文献   

10.
Two molybdophosphate compounds,[Ni(bim)3]2[H2P2Mo5O23]·2H2O 1 and [Zn(bpy)2]2[Zn(bpy)(H2O)]2Zn[Mo6O12(OH)3(HPO4)4]2·9H2O 2 (bim = 2,2'-biimidazole,bpy = 2,2'-dipyridyl),have been synthesized under hydrothermal conditions and structurally characterized by elemental analysis,TG,and IR. The single-crystal X-ray analysis exhibits that 1 consists of one [H2P2Mo5O23]4-,two [Ni(bim)3]2+ cations and two lattice water molecules,while 2 is constructed from one sandwich-type [ZnP4Mo6] anion modified by four Zn-bpy complexes and nine lattice water molecules. The electrochemical behaviors of compounds 1 and 2 have been studied in detail based on solid bulk modified carbon paste electrodes of compound (CPEs).  相似文献   

11.
Two novel compounds 1-(4-fluorobenzyl)-4-chloro-(Z)-3-benzoylhydrazono-2-indolinone(1) and 1-(4-methoxybenzyl)-(Z)-3-benzoylhydrazono-2-indolinone(2) were synthesized and their crystal structures were determined by single-crystal X-ray diffraction.Compound 1(C22H15ClFN3O2) crystallized in the triclinic system,space group P1·with a=0.94198(19) nm,b=1.4339(3) nm,c=1.5018(3) nm,α=101.58(3)°,β=102.96(3)°,γ=102.73°,V=1.8602(6) nm3,Mr=407.82,Dc=1.456 g/cm3,μ=0.240 mm-1,F(000)=840,Z=4,R1=0.0442 and wR2=0.1064.Comp...  相似文献   

12.
Summary. Crystal structure determinations of two novel bilirubin analogs with spirocyclohexyl and spirofluorenyl groups at C(10) are reported. Conformation-determining torsion angles and key hydrogen bond distances and angles are compared to those from molecular dynamics calculations, and to the corresponding data from X-ray determinations and molecular dynamics calculations of bilirubin. Like bilirubin, the component dipyrrinones of spirocyclohexyl and spirofluorenyl rubins are present in the bis-lactam form with (Z)-configuration double bonds at C(4) and C(15). Their crystal structures show considerable similarity to that of bilirubin: both pigments adopt a folded, intramolecularly hydrogen-bonded ridge-tile conformation stabilized by six hydrogen bonds. The interplanar angle of the spirocyclohexyl ridge-tile is nearly the same (94°) as that of bilirubin (95°), but the interplanar angle of the spirofluorenyl ridge-tile is noticeably smaller (84°). The hydrogen bond distances of both spiro-rubin crystal structures are generally longer by 0.1–0.2Å than those in bilirubin. Both new pigments exhibit excellent lipophilicity and, unlike bilirubin, are soluble in methanol.  相似文献   

13.
In recent years, cocrystallization has emerged as an effective way of tuning the properties of compounds and has been widely used in the field of energetic materials. In this study, we have prepared two novel cocrystals of CL‐20 and methylimidazole, including a 1:2 CL‐20 / 2‐mercapto‐1‐methylimidazole ( 1 ) and a 1:4 CL‐20 / 4‐methyl‐5‐nitroimidazole ( 2 ). Cocrystal 1 has good physical and detonation properties (ρ1 = 1.652 g · cm–3, D1 = 7073 m · s–1, P1 = 21.6 GPa); however, cocrystal 2 shows higher properties (ρ2 = 1.680 g · cm–3, D2 = 7945 m · s–1, P2 = 27.4 GPa). The performance of both cocrystals is better than those of TNT. Thermal performance suggests that both the cocrystals have moderate thermal stabilities. Cocrystal 1 decomposes at 164.9 °C and cocrystal 2 has an exothermic peak at 221 °C. Both cocrystals are insensitive energetic explosives (IS > 40 J, FS > 360 N). Methylimidazole compounds are rarely used as coformers to form cocrystals with CL‐20, which possess good properties for a range of potential applications. Herein, we provide new possible directions for enriching cocrystal speciation.  相似文献   

14.
Summary. Bilirubin congeners with dipyrrinones conjoined to a diaceteylene unit (–CC–CC–) rather than to –CH2– were synthesized and examined spectroscopically. This new class of rubrified linear tetrapyrroles cannot easily fold or bend in the middle, but the dipyrrinones can rotate independently about the diacetylene unit. Thus, unlike bilirubin, which is bent in the middle and has a ridge-tile shape, the diacetylene unit orients the attached dipyrrinones along a linear path, and intramolecular hydrogen bonding between the dipyrrinones and opposing carboxylic acids preserves a twisted linear molecular shape when the usual propionic acids are replaced by hexanoic. In a bis-hexanoic acid rubin, the extended planes of the dipyrrinones intersect along the –(CC)2– axis at an angle of 102° for the conformation stabilized by intramolecular hydrogen bonding. With propionic acid chains, however, neither CO2H can engage an opposing dipyrrinone in intramolecular hydrogen bonding, and the energy-minimum conformation of this linear pigment, shows nearly co-planar dipyrrinones, with an intersection of an angle of 180° of the extended planes of the dipyrrinones. Spectroscopic evidence for such linearized and twisted (bis-hexanoic) and planar (bis-propionic) structures comes from the pigments NMR spectral data and their exciton UV-Vis and induced circular dichroism spectra.  相似文献   

15.
Two new dinuclear MnII cluster-based metal-organic frameworks, namely [Mn2(L)(DMPU)3]n ( 1 ) and [Mn(L)0.5(4,4'-bipy)0.5(H2O)]n ( 2 ) (H4L = biphenyl-3,3',5,5'-tetracarboxylic acid, DMPU = 1,3-dimethyltetrahydropyrimidin-2(1H)-one, 4,4'-bipy = 4,4'-bipyridine), were solvothermally synthesized and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, and magnetic studies. Compound 1 crystallizes in the monoclinic P21/n space group and displays a 3D framework with 4-connected crb/BCT -type topology, and compound 2 crystallizes in the monoclinic C2/c space group and displays a 3D framework with (4,6)-connected sqc422 -type topology. The magnetic studies of compounds 1 and 2 show the presence of weak antiferromagnetic interactions within the dinuclear MnII units.  相似文献   

16.
Mg2(PO2NH)4 · 8 H2O ( 1 ), Mn2(PO2NH)4 · 8 H2O ( 2 ), Co2(PO2NH)4 · 8 H2O ( 3 ) and Zn2(PO2NH)4 · 8 H2O ( 4 ) were obtained as microcrystalline powders by combining aqueous solutions of K4(PO2NH)4 · 4 H2O and MX2 · y H2O (M = Mg, Mn, Co, Zn; X = Cl, NO3). Single crystals were obtained by crystallization in gelatine gels in U‐tubes or test‐tubes. 2 and 4 were characterized by thermogravimetry and 4 was additionally characterized by temperature dependend in situ powder diffractometry. The structures of 1 , 2 , 3 and 4 were found to be isotypic and were solved by single‐crystal X‐ray methods: P 21/c, Z = 2 ( 1 : a = 645.4(2), b = 1050.1(2), c = 1283.3(3) pm, β = 104.66(3)°; 2 : a = 648.7(2), b = 1063.1(2), c = 1310.8(3) pm, β = 103.93(3)°; 3 : a = 643.3(2), b = 1049.0(2), c = 1286.7(3) pm, β = 104.28(3)°; 4 : a = 644.18(5), b = 1049.22(7), c = 1282.43(8) pm, β = 104.122(6)°). The structure is composed of MO6 octahedra and (PO2NH)44— anions. The P4N4 rings of the (PO2NH)44— anions exhibit a slightly distorted chair conformation, which is supported by IR data and has been described by torsion angles, Displacement Asymmetry Parameters and Puckering Parameters. Via M2+ ions and hydrogen bonds, the tetrametaphosphimate anions are connected forming layers perpendicular to [100]. These layers are connected by hydrogen bonds.  相似文献   

17.
A novel complex [Li3{μ‐(H2O)6}(H2O)6]·[RuCl6] has been synthesized and was characterized by single‐crystal X‐ray diffraction. The compound crystallizes in rhombohedral space group Rc, with the unit cell parameters a = b = 9.948(2)Å, c = 33.376(14)Å, γ = 120°, V = 2860.5(15)Å3, Z = 6, Dc = 1.918 Mg m—3, μ = 1.703 mm—1, R = 0.0244, wR = 0.0478. The compound consists of a cation, which contains three lithium ions linked by six bridged water molecules, and an anion, which contains a ruthenium(III) ion. The whole complex can be described as a three‐dimensional structure linked by hydrogen bonds between cation and anion. The magnetic properties of the complex have been investigated. The IR, UV‐vis and EPR spectra are studied.  相似文献   

18.
Two heterometallic 3d–4f coordination polymers, [Gd(CuL)2(Hbtca)(btca)(H2O)] · 2H2O ( 1 ) and [Er(CuL)2(Hbtca)(btca)(H2O)] · H2O · CH3OH ( 2 ) (CuL, H2L = 2,3‐dioxo‐5,6,14,15‐dibenzo‐1,4,8,12‐tetraazacyclo‐pentadeca‐7,13‐dien; H2btca = benzotriazole‐5‐carboxylic acid) were synthesized by solvothermal methods and characterized by single‐crystal X‐ray diffraction. Complexes 1 and 2 exhibit a double‐strand meso‐helical chain structures formed by [LnIIICuII2] (LnIII = Gd, Er) units by oxamide and benzotriazole‐5‐carboxylate bridges. They are isomorphic except that one free water molecule of 1 is replaced by a methanol molecule. All 1D chains are further interlinked by hydrogen bonds resulting in a 3D supramolecular architecture. The magnetic properties of the compound 1 and 2 are also discussed.  相似文献   

19.
通过四水乙酸钴(Ⅱ)和Salamo型双肟配体4,4''-二硝基-2,2''-(1,2-乙二氧双(氮次甲基))二酚(H2L)在不同溶剂中的配位反应,合成了2种不同溶剂参与配位的三核钴(Ⅱ)配合物,即[Co3L(OAc)2(CH3CH2OH)2]·2CH3CH2OH·2CHCl31)和[Co3L(OAc)2(C3H7OH)2](2),并通过元素分析、红外光谱、紫外-可见光谱和单晶X射线衍射法对其进行了性质表征。在配合物12中,存在2个配体单元(提供N2O2配位原子),2个乙酸根离子,2个配位的乙醇或正丙醇分子。虽然2个配合物是在不同溶剂中合成的,但配合物中的钴(Ⅱ)离子均采用稍微扭曲的八面体几何构型。结果表明,溶剂效应在配合物的配位环境中起了关键的作用。另外,配合物12在激发波长为450 nm时能表现出强烈的光致发光,其最大发射波长分别为568和566 nm。  相似文献   

20.
Two complexes,Co(Hbim)2(NCS)2(Hbim=benzimidazole)(1) and [Cu(Hbzt)SCN]n(Hbzt=benzothiazole) (2) were synthesized by the same synthesis method and characterized by elemental analysis,infrared spectroscopy(IR),thermogravimetric analysis(TGA),X-ray powder diffraction(XRPD) and single-crystal X-ray diffraction.The results from the single-crystal X-ray diffraction indicate that complex 1 is zero-dimensional(0D) framework and complex 2 is 2-dimensional(2D) framework.In complex 2,the 3-dimensional(3D) supermolecular architecture was built up by means of π-π stacking interaction,and two helical chains existed in its structure.The luminescence properties and the magnetic properties of the two complexes were investigated.  相似文献   

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