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1.
Three multi‐dentate 1, 2,4‐triazole derivative ligands containing different 4‐substituted groups, namely N‐1, 2,4‐triazol‐4‐yl(pyridin‐3‐yl)methylenimine (L1), N‐1, 2,4‐triazol‐ 4‐yl(pyridin‐4‐yl)methylenimine (L2), and 4‐(2‐pyridine)‐1, 2,4‐triazole (L3) were used to isolate five iron(II) and zinc(II) coordination frameworks, [Zn(μ2‐L1)Cl2] ( 1 ), [Zn(μ2‐L2)Br2] ( 2 ), [Fe(L1)2(NCS)2(H2O)2] ( 3 ), [Fe(L3)2(dca)2(H2O)2] ( 4 ), and [Fe(L3)2(μ2‐dca)] ( 5 ) (dca = dicyanamide anion). When different zinc(II) salts were used to react with L1 and L2 under solvothermal conditions, two one‐dimensional (1D) zinc(II) coordination frameworks 1 and 2 containing four‐coordinate central zinc(II) atoms were isolated. 1 is a 3D achiral supra‐molecular framework, whereas 2 is a 3D chiral supra‐molecular framework containing helical chains on a 21 axis. 3 is a mono‐nuclear iron(II) coordination framework containing six‐coordinate central FeII atoms. When L3 was employed, mono‐nuclear iron(II) framework 4 and 1D iron(II) chain 5 could be isolated when different amounts of Nadca were introduced into the reaction system. Variable‐temperature magnetic susceptibility data of 3 – 5 were recorded in the 2–300 K temperature range indicating weak anti‐ferromagnetic interactions. The solid‐state luminescent properties of coordination polymers 1 and 2 were also investigated at room temperature.  相似文献   

2.
The amino substituted bidentate chelating ligand 2‐amino‐5‐(2‐pyridyl)‐1,3,4‐thiadiazole (H2 L ) was used to prepare 3:1‐type coordination compounds of iron(II), cobalt(II) and nickel(II). In the iron(II) perchlorate complex [FeII(H2 L )3](ClO4)2·0.6MeOH·0.9H2O a 1:1 mixture of mer and fac isomers is present whereas [FeII(H2 L )3](BF4)2·MeOH·H2O, [CoII(H2 L )3](ClO4)2·2H2O and [NiII(H2 L )3](ClO4)2·MeOH·H2O feature merely mer derivatives. Moessbauer spectroscopy and variable temperature magnetic measurements revealed the [FeII(H2 L )3]2+ complex core to exist in the low‐spin state, whereas the [CoII(H2 L )3]2+ complex core resides in its high‐spin state, even at very low temperatures.  相似文献   

3.
Using the ligands N‐methylimidazole ( MeIm ), N‐ethylimidazole ( EtIm ), N‐propylimidazole ( PrIm ), and 1‐methyl‐1H‐1, 2, 4‐triazole ( MeTz ) three series with a total of 13 iron(II) complexes were isolated. The series comprise of the following complexes: (a) [Fe( MeIm )6](ClO4)2 ( 1 ), [Fe( EtIm )6](ClO4)2 ( 2 ), [Fe( PrIm )6](ClO4)2( 3 ), [Fe( MeTz )6](ClO4)2 ( 4 ), [Fe( MeIm )6](MeSO3)2 ( 5 ), [Fe( EtIm )6](MeSO3)2 ( 6 ), and [Fe( MeTz )6](BF4)2 ( 10 ); (b) [Fe( MeIm )4(MeSO3)2]( 7 ), [Fe( EtIm )4(MeSO3)2] ( 8 ), and [Fe( PrIm )4(MeSO3)2] ( 9 ); (c) [Fe( MeIm )4(NCS)2] ( 15 ), [Fe( EtIm )4(NCS)2] ( 16 ), and [Fe( MeTz )4(NCS)2] ( 17 ). Single crystal X‐ray diffraction studies were performed on 7 – 10 and 15 – 17 . Temperature dependent magnetic susceptibility measurements were performed on selective examples of all series, and confirmed them to be in the HS state over the range 6–300 K. DFT calculations were performed at BP86/def‐SV(P) and TPSSh/def2‐TZVPP level on all [Fe L 6]2+ complex cations and the neutral complexes 7 – 9 and 15 – 17 . Additionally the four homoleptic nickel(II) complexes [Ni L 6](ClO4)2 ( 11 : L = MeIm ; 12 : L = EtIm ; 13 : L = PrIm ; 14 : L = MeTz ) were synthesized and compounds 11 – 13 structurally characterized. UV/Vis/NIR spectroscopic measurements were carried out on all homoleptic iron(II) and nickel(II) complexes. The 10Dq values were determined to be in the range of 11547–11574 and 10471–10834 cm–1 for the iron(II) and nickel(II) complexes, respectively.  相似文献   

4.
Hydrothermal reactions of tridentate rigid 2,4,6‐tris‐(benzimidazolyl‐2‐yl)pyridine (pytbzim) ligand and Zn(II)/Cd(II) salts generate binuclear complexes {[Cd2Cl2(pytbzim)2(H2O)2]·2NO3}n ( 1 ) and two isomorphs {[M2Cl2(pytbzim)2(H2O)2]Cl2·2H2O}n [M=Cd ( 2 ), Zn ( 3 )]. All complexes include [M2Cl2(pytbzim)2(H2O)2] dimers, which are further connected into a three‐dimensional supramolecular networks through ?‐? stacking interaction and hydrogen bonds. The solid state photoluminescent studies reveal good fluorescent properties of the pytbzim ligand and complexes 1 – 2 at room temperature.  相似文献   

5.
Three 1H‐benzimidazole‐5‐carboxylate (Hbic–)‐based coordination polymers, {[Ni(H2O)(Hbic)2] · 2H2O}n ( 1 ), {[Ni(H2O)2(Hbic)2] · 3H2O}n ( 2 ), and {[Co2(H2O)4(Hbic)4] · 4DMF · 3H2O}n ( 3 ) were obtained by reactions of the ligand H2bic and NiII or CoII salts in the presence of different structure directing molecules. They were structurally characterized by single‐crystal X‐ray diffraction, IR spectra, elemental analysis, thermal stability, luminescent, and magnetic measurements. Structural analysis suggests that the three polymers exhibit a 2D (4, 4) layer for 1 and 1D linear double chains for both 2 and 3 due to the variable binding modes and the specific spatial orientation of the Hbic– ligand towards the different paramagnetic metal ions, which were further aggregated into different 3D supramolecular architectures by popular hydrogen‐bonding interactions. Weak and comparable antiferromagnetic couplings mediating by Hbic– bridge are observed between the neighboring spin carriers for 2 and 3 , respectively. Additionally, complexes 1 – 3 also display different luminescence emissions at room temperature due to the ligand‐to‐metal charge transfer.  相似文献   

6.
The coordination polymers, {[Co(bbim)2(H2O)2](tcbdc) · 2H2O}n ( 1 ), {[Ni(tcbdc)(bbim)(H2O)2] · 2DMF}n ( 2 ), and {[Cu2(tcbdc)2(bbim)4] · 4H2O}n ( 3 ) [bbim = 1,1′‐(1,4‐butanediyl)bis(imidazole) and tcbdc2– = tetrachlorobenzene‐1,4‐dicarboxylate] were synthesized and characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, luminescence, and single‐crystal X‐ray diffraction analysis. Complex 1 has a double‐stranded chain structure through doubly bridged [Co(bbim)2] units. Complex 2 exhibits two‐dimensional square grid, whereas complex 3 has a three‐dimensional porous network structure with an unprecedented 44 · 611 topological structure through interpenetrating square grid. The water molecules in complex 3 occupy the vacancy through three kinds of hydrogen bond interactions. Upon excitation at 370 nm, complexes 1 – 3 present solid‐state luminescence at room temperature.  相似文献   

7.
The zinc(II) pseudohalide complexes {[Zn(L334)(SCN)2(H2O)](H2O)2}n ( 1 ) and [Zn(L334)(dca)2]n ( 2 ) were synthesized and characterized using the ligand 3,4‐bis(3‐pyridyl)‐5‐(4‐pyridyl)‐1,2,4‐triazole (L334) and ZnCl2 in presence of thiocyanate (SCN–) and dicynamide [dca, N(CN)2–] respectively. Single‐crystal X‐ray structural analysis revealed that the central ZnII atoms in both complexes have similar octahedral arrangement. Compound 1 has a 2D sheet structure bridged by bidentate L334 and double μN,S‐thiocyanate anions, whereas complex 2 , incorporating with two monodentate dicynamide anions, displays a two‐dimensional coordination framework bridged by tetradentate L334 ligand. Structural analysis demonstrated that the influence of pseudohalide anions plays an important role in determining the resultant structure. Both complexes were characterized by IR spectroscopy, microanalysis, and powder X‐ray diffraction techniques. In addition, the solid fluorescence and thermal stability properties of both complexes were investigated.  相似文献   

8.
Two new transition metal dicyanamide complexes [Co2(tppz)(dca)4]·CH3CN ( 1 ) [tppz=tetra(2‐pyridyl)pyrazine, dca=dicyanamide] and [Co(tptz)(dca)(H2O)](dca) ( 2 ) [tptz=2,4,6‐tri(2‐pyridyl)‐1,3,5‐triazine] were synthesized and characterized by single crystal X‐ray diffraction analysis. In 1 each cobalt(II) atom is coordinated to three dca anions and one tppz molecule to form a distorted octahedral geometry, the neigbour two cobalt(II) atoms are bridged by one tppz ligand to form a dimer, then the cobalt(II) atoms in each dimer are joined together to form a ladder chain structure. In 2 the coordination geometry around the central metal is also distorted octahedral, each cobalt(II) atom is coordinated by two dca anions, one tptz molecule and one water ligand to form a cationic part, and the cationic part is linked with the free dca anions via the electrostatic attraction to give an infinite chain structure. Magnetic susceptibility measurement in the range of 2–300 K indicates that there are antiferromagnetic couplings between adjacent metal ions in 1 (T>29 K, (=?9.78 K, C=4.92 cm3·K·mol?1) and ferromagnetic couplings in 2 (T>150 K, (=7.97 K, C=2.59 cm3·K·mol?1) respectively.  相似文献   

9.
Three 3‐amino‐1, 2, 4‐triazole (atz)‐based paramagnetic complexes, [Mn(atz)(pa)]n ( 1 ), {[Mn(atz)1.5(hip)] · H2O}n ( 2 ), and [Mn(H2O)2(atz)2(nb)2] ( 3 ) (H2pa = o‐phthalic acid, H2hip = 5‐hydroxylisophthalic acid, and Hnb = p‐nitrobenzoic acid) were prepared by introducing different carboxylate‐containing aromatic coligands, and structurally and magnetically characterized. Helical MnII‐atz and bent MnII‐pa2– chains are crosslinked by sharing the same metal sites to generate a honeycomb‐shaped framework of 1 . The undulated MnII‐atz layers constructed from 22‐member metallomacrocycles are periodically supported by ditopic hip2– ligands to lead to a pillared‐layer structure of 2 . In contrast, complex 3 is a centrosymmetric mononuclear entity, which is assembled into a three‐dimensional supramolecular network by abundant hydrogen‐bonding interactions. The structural difference of 1 – 3 is significantly due to the combinations of the flexible coordination modes adopted by the mixed atz and carboxylate groups. Weak and comparable antiferromagnetic couplings are observed in the nearest neighbors of 1 – 3 , which are cooperatively transmitted either by short carboxylate and/or atz heterobridges or by weak non‐covalent interactions.  相似文献   

10.
The coordination polymers (CPs), [Ni(L)(H2O)4]n ( 1 ), [Co(HL)2(H2O)2]n ( 2 ), {[Cu(L)(H2O)3] · H2O}n ( 3 ), [Mn(L)(H2O)2]n ( 4 ), [Cd(L)(H2O)2]n ( 5 ), and {[Zn2(L)2] · H2O}n ( 6 ), were solvothermally synthesized by employing the imidazol‐carboxyl bifunctional ligand 4‐(1H‐imidazol‐1‐yl) phthalic acid (H2L). Single‐crystal X‐ray diffraction indicated that the L2–/HL– ligands display various coordination modes with different metal ions in 1 – 6 . Complexes 1 and 2 show one‐dimensional (1D) chain structures, whereas complexes 3 – 6 show 2D layered structures. The magnetic properties of these complexes were investigated. Complexes 1 and 3 indicate weak ferromagnetic interactions, whereas complexes 2 and 4 demonstrate antiferromagnetic interactions. In addition, luminescence properties of 5 and 6 were measured and studied in detail.  相似文献   

11.
1‐(2‐Hydroxyethyl)‐3‐nitro‐1, 2, 4‐triazole (hnt), prepared by alkylation of 3‐nitro‐1, 2, 4‐triazole with 2‐chloroethanol, was found to react with copper(II) chloride and copper(II) perchlorate in acetonitrile/ethanol solutions giving complexes [Cu2(hnt)2Cl4(H2O)2] and[Cu(hnt)2(H2O)3](ClO4)2, respectively. They are the first examples of coordination compounds with a neutral N‐substituted 3‐nitro‐1, 2, 4‐triazole ligand. 1‐(2‐Hydroxyethyl)‐3‐nitro‐1, 2, 4‐triazole and the obtained complexes were characterized by NMR and IR spectroscopy, X‐ray, and thermal analyses. [Cu2(hnt)2Cl4(H2O)2] presents a dinuclear chlorido‐bridged complex in which hnt acts as a chelating bidentate ligand, coordinated to the metal by a nitrogen atom of the triazole ring and an oxygen atom of the nitro group, and the copper atoms are inconsiderably distorted octahedral coordination. [Cu(hnt)2(H2O)3](ClO4)2comprises a mononuclear complex cation, in which two nitrogen atoms of two hnt ligands in trans configuration and three water oxygen atoms form a square pyramidal environment around the copper atom, which is completed to an distorted octahedron with a bifurcated vertex due to two additional elongated Cu–O bonds with two nitro groups. In both complexes, Cu–O bonds with the nitro groups may be considered as semi‐coordinated.  相似文献   

12.
Abstract. Two bis‐triazole‐bis‐amide‐based copper(II) pyridine‐2,3‐dicarboxylate coordination polymers (CPs), [Cu(2,3‐pydc)(dtb)0.5(DMF)] · 2H2O ( 1 ) and [Cu(2,3‐pydc)(dth)0.5(DMF)] · 2H2O ( 2 ) (2,3‐H2pydc = pyridine‐2,3‐dicarboxylic acid, dtb = N,N′‐bis(4H‐1,2,4‐triazole)butanamide, and dth = N,N′‐bis(4H‐1,2,4‐triazole)hexanamide), were synthesized under solvothermal conditions. CPs 1 and 2 show similar two‐dimensional (2D) structures. In 1 , the 2,3‐pydc anions bridge the CuII ions into a one‐dimensional (1D) chain. Such 1D chains are linked by the dtb ligands to form a 2D layer. The adjacent 2D layers are extended into a three‐dimensional (3D) supramolecular architecture by hydrogen‐bonding interactions. The electrochemical properties of 1 and 2 were investigated.  相似文献   

13.
热力学稳定的带有大环配体的μ－氧桥联－双铁配合物，由于其两个铁中心之间的有趣的电子结构和磁相互作用而受到广泛关注。μ－氧桥联－双铁席夫碱配合物，[{Fe(tbusalphn)}2(μ-o)] (1)和[{Fe(R,R-salchxn)}2(μ-o)] (2), 通过用咪唑或N－甲基咪唑的水溶液处理相应的单核铁氯化物，Fe(L)Cl，而获得。1和2的晶体结构通过x-射线结构分析而被确定。1属于三斜晶系，P－1空间群。2属于单斜晶系，P21/c空间群。由于1的配体带有庞大的叔丁基取代基，导致形成μ－氧桥联－双铁配合物时的空间拥挤，因此，其Fe-O-Fe夹角为176.5 o，几乎成平角。而2则由于配体上没有庞大的取代基，其Fe-O-Fe夹角为149.6o，明显小于1的Fe-O-Fe夹角。 本文还对两种μ－氧桥联－双铁席夫碱配合物及相应的单核铁氯化物的红外光谱、紫外－可见吸收光谱及圆二色光谱性质进行了研究。与相应的单体铁配合物相比较，生成μ－氧桥联－双铁席夫碱配合物后，出现一新的红外吸收带，归属于νFe-O-Fe振动。有趣的是，其数值与Fe-O-Fe夹角大小相对应。1和2除具有明显不同的Fe-O-Fe夹角外，它们的圆二色光谱却是相似的。 对1和2的磁性质研究表明，在这类化合物中两个铁(III)离子之间存在着强烈的分子内抗铁磁性偶合作用。另外，本文还采用循环伏安法对1和2的电化学性质进行了研究。  相似文献   

14.
Three metal coordination polymers {[Co(L)2(H2O)2]2+ · 2NO3–}n ( 1 ), {[Mn(L)2(H2O)2]2+ · 2Cl– · 3H2O}n ( 2 ), and [ZnL(ba)2]n ( 3 ) [L = 3,5‐bis(imidazole‐1‐yl)pyridine and Hba = benzoic acid] were synthesized and structurally characterized by IR spectroscopy, elemental analysis, X‐ray powder diffraction, and X‐ray single crystal diffraction. Complex 1 shows a one‐dimensional (1D) chain structure. Adjacent chains are connected by hydrogen bonding and nitrate groups to form a 3D network. Complex 2 features a 2D layer structure. A three‐dimensional network is constructed through the cluster consisting of two chloride ions and three water molecules. Complex 3 shows a 1D zigzag chain structure that further twists together to form a 3D network. The X‐ray powder diffraction patterns were compared with the simulated ones. Moreover, the luminescent properties of 1 – 3 were investigated in the solid state at room temperature, and the thermogravimetric analyses were carried out to study the thermal stability of the three complexes.  相似文献   

15.
Two complexes based on the ligand 1,4‐dihydro‐2,3‐quinoxalinedione, namely [Mn(H2L)2(H2O)2]n ( 1 ) and {[Zn2(H2L)2(tz)2] · 5H2O}n ( 2 ) (H3L = 2,3‐dioxo‐1,2,3,4‐tetrahydroquinoxaline‐6‐carboxylic acid, Htz = 1,2,4‐triazole) were hydrothermally synthesized and characterized by elemental analyses, IR spectroscopy, as well as single‐crystal and powder X‐ray diffraction. Complex 1 exhibited a 1D comb‐like chain formed by H2L– anions linking MnII ions, whereas complex 2 was a 2D layer‐like structure with square‐shaped windows and outstretched arms built by combination of H2L– and tz– ligands with ZnII ions. The adjacent chains or layers connected with each other by intermolecular hydrogen bonding and π–π stacking to further extend to a 3D supermolecular framework. In addition, the thermal stabilities, luminescence properties, and optical energy gap of 1 and 2 were investigated in detail.  相似文献   

16.
Three new one‐ (1D) and two‐dimensional (2D) CuII coordination polymers, namely poly[[bis{μ2‐4‐amino‐3‐(pyridin‐2‐yl)‐5‐[(pyridin‐3‐ylmethyl)sulfanyl]‐1,2,4‐triazole}copper(II)] bis(methanesulfonate) tetrahydrate], {[Cu(C13H12N5S)2](CH3SO3)2·4H2O}n ( 1 ), catena‐poly[[copper(II)‐bis{μ2‐4‐amino‐3‐(pyridin‐2‐yl)‐5‐[(pyridin‐4‐ylmethyl)sulfanyl]‐1,2,4‐triazole}] dinitrate methanol disolvate], {[Cu(C13H12N5S)2](NO3)2·2CH3OH}n ( 2 ), and catena‐poly[[copper(II)‐bis{μ2‐4‐amino‐3‐(pyridin‐2‐yl)‐5‐[(pyridin‐4‐ylmethyl)sulfanyl]‐1,2,4‐triazole}] bis(perchlorate) monohydrate], {[Cu(C13H12N5S)2](ClO4)2·H2O}n ( 3 ), were obtained from 4‐amino‐3‐(pyridin‐2‐yl)‐5‐[(pyridin‐3‐ylmethyl)sulfanyl]‐1,2,4‐triazole with pyridin‐3‐yl terminal groups and from 4‐amino‐3‐(pyridin‐2‐yl)‐5‐[(pyridin‐4‐ylmethyl)sulfanyl]‐1,2,4‐triazole with pyridin‐4‐yl terminal groups. Compound 1 displays a 2D net‐like structure. The 2D layers are further linked through hydrogen bonds between methanesulfonate anions and amino groups on the framework and guest H2O molecules in the lattice to form a three‐dimensional (3D) structure. Compound 2 and 3 exhibit 1D chain structures, in which the complicated hydrogen‐bonding interactions play an important role in the formation of the 3D network. These experimental results indicate that the coordination orientation of the heteroatoms on the ligands has a great influence on the polymeric structures. Moreover, the selection of different counter‐anions, together with the inclusion of different guest solvent molecules, would also have a great effect on the hydrogen‐bonding systems in the crystal structures.  相似文献   

17.
The reaction of 4‐amino‐3,5‐bis(imidazol‐1‐ylmethyl)‐1,2,4‐triazole (abit) and manganese(II) salts yields four coordination polymers {[Mn(abit)3](ClO4)2}n ( 1 ), {[Mn(abit)3](PF6)2}n ( 2 ), [Mn(abit)(dca)2(H2O)2]n ( 3a ) and [Mn(abit)(dca)2(H2O)2]n ( 3b ). Compounds 1 and 2 are one‐dimensional triple‐stranded chain. Compounds 3a and 3b are polymorphous and construct one‐dimensional single chain. The conformational analysis is performed. The thermal properties have been investigated.  相似文献   

18.
Based on the 2,6‐bis(pyrazol‐3‐yl)pyridine ligand (H2bpp) the hexanuclear iron(III) complex [Fe6(bpp)4(μ3‐O)2(μ‐OMe)3(μ‐OH)Cl2] ( 1 ) was synthesized. The reaction with iron(II) chloride and additional pyridine leads to the exclusive formation of the complex through self‐assembly process. Six octahedrally coordinated iron atoms are linked through the pyrazolido groups of four H2bpp ligands. These are further linked through bridging hydroxido, methoxido, and oxido groups. The complex has been characterized by IR spectroscopy, ESI mass spectrometry, elemental analysis and X‐ray crystallography. Temperature‐dependent magnetic measurements indicate strong antiferromagnetic exchange interaction between the high‐spin iron(III) ions within the complex, which leads to an S = 0 spin ground state. As a result of the two Fe3(μ3‐O) fragments two frustrated exchange pathways are present. In addition the properties of H2bpp as a potential capping ligand for the synthesis of heteroleptic trinuclear complexes based on the triaminoguanidine core is investigated.  相似文献   

19.
Because of their versatile coordination modes and strong coordination ability for metals, triazole ligands can provide a wide range of possibilities for the construction of metal–organic frameworks. Three transition‐metal complexes, namely bis(μ‐1,2,4‐triazol‐4‐ide‐3‐carboxylato)‐κ3N 2,O :N 1;κ3N 1:N 2,O‐bis[triamminenickel(II)] tetrahydrate, [Ni2(C3HN3O2)2(NH3)6]·4H2O, (I), catena‐poly[[[diamminediaquacopper(II)]‐μ‐1,2,4‐triazol‐4‐ide‐3‐carboxylato‐κ3N 1:N 4,O‐[diamminecopper(II)]‐μ‐1,2,4‐triazol‐4‐ide‐3‐carboxylato‐κ3N 4,O :N 1] dihydrate], {[Cu2(C3HN3O2)2(NH3)4(H2O)2]·2H2O}n , (II), (μ‐5‐amino‐1,2,4‐triazol‐1‐ide‐3‐carboxylato‐κ2N 1:N 2)di‐μ‐hydroxido‐κ4O :O‐bis[triamminecobalt(III)] nitrate hydroxide trihydrate, [Co2(C3H2N4O2)(OH)2(NH3)6](NO3)(OH)·3H2O, (III), with different structural forms have been prepared by the reaction of transition metal salts, i.e. NiCl2, CuCl2 and Co(NO3)2, with 1,2,4‐triazole‐3‐carboxylic acid or 3‐amino‐1,2,4‐triazole‐5‐carboxylic acid hemihydrate in aqueous ammonia at room temperature. Compound (I) is a dinuclear complex. Extensive O—H…O, O—H…N and N—H…O hydrogen bonds and π–π stacking interactions between the centroids of the triazole rings contribute to the formation of the three‐dimensional supramolecular structure. Compound (II) exhibits a one‐dimensional chain structure, with O—H…O hydrogen bonds and weak O—H…N, N—H…O and C—H…O hydrogen bonds linking anions and lattice water molecules into the three‐dimensional supramolecular structure. Compared with compound (I), compound (III) is a structurally different dinuclear complex. Extensive N—H…O, N—H…N, O—H…N and O—H…O hydrogen bonding occurs in the structure, leading to the formation of the three‐dimensional supramolecular structure.  相似文献   

20.
Three coordination polymers, namely {[Cu(5‐nipa)(L22)](H2O)2}n ( 1 ), [Zn(5‐nipa)(L22)(H2O)]n ( 2 ), and {[Cd2(5‐nipa)2(L22)(H2O)3](H2O)3.6}n ( 3 ), were prepared under similar synthetic method based on 1,2‐(2‐pyridyl)‐1,2,4‐triazole (L22) and ancillary ligand 5‐nitro‐isophthalic acid (5‐H2nipa) with CuII, ZnII, and CdII perchlorate, respectively. All the complexes were characterized by IR spectroscopy, elemental analysis, and powder X‐ray diffraction (PXRD) patterns. Single‐crystal X‐ray diffraction indicates that complexes 1 and 2 show similar 1D chain structures, whereas complex 3 exhibits the 2D coordination network with hcb topology. The central metal atoms show distinct coordination arrangements ranging from distorted square‐pyramid for CuII in 1 , octahedron for ZnII in 2 , to pentagonal‐bipyramid for CdII in 3 . The L22 ligand adopts the same (η3,μ2) coordination fashion in complexes 1 – 3 , while the carboxyl groups of co‐ligand 5‐nipa2– adopt monodentate fashion in 1 and 2 and bidentate chelating mode in 3 . These results indicate that the choice of metal ions exerts a significant influence on governing the target complexes. Furthermore, thermal stabilities of complexes 1 – 3 and photoluminescent properties of 2 and 3 were also studied in the solid state.  相似文献   

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