This paper obtains the lowest-energy geometric structures and the electronic and magnetic properties of small CuNiN clusters by using all-electron density functional theory. The calculated results reveal that the Cu a...This paper obtains the lowest-energy geometric structures and the electronic and magnetic properties of small CuNiN clusters by using all-electron density functional theory. The calculated results reveal that the Cu atom prefers to occupy the apical site when N ≤ 9 and for the clusters with N = 10, the Cu atom starts to encapsulate in the cage. The CuNi7 and CuNi9 are magic clusters. The magnetism correlates closely with the symmetry of the clusters. For these clusters, the charge tends to transfer from the nickel atoms to the copper atoms. It finds that the doping of Cu atom decreases the stability of pure NiN clusters.展开更多
Based on the reported Fe clusters constructed by using N-tris(hydroxymethyl)methylglycine (H_5thmmg),herein,we explored the use of H_5 thmmg for Ni chemistry.Successfully,an octanuclear Ni cluster,Ni_(8)O(H_(3)thmmg)_...Based on the reported Fe clusters constructed by using N-tris(hydroxymethyl)methylglycine (H_5thmmg),herein,we explored the use of H_5 thmmg for Ni chemistry.Successfully,an octanuclear Ni cluster,Ni_(8)O(H_(3)thmmg)_6·2NO_(3)(Ni_(8)) was acquired under solvothermal condition.Its metallic core is comprised of two centrosymmetric cubanes Ni_(4)(μ_(3)-O)_(3)(μ_6-O) linked by sharing an O^(2-)ion and six H_(3)thmmg^(2-) ligands are attached to the periphery.Interestingly,the 2-mercapto-5-amino-1,3,4-thiadiazole (Hmat) ligand with both N and S donor atoms was introduced into the synthesis of Ni_(8) cluster,a disparate decanuclear nickel cluster,Ni_(10)O(OH)_(2)(H_(3)thmmg)_(4)(mat)_(8)(Ni_(10)) is assembled by H_(3)thmmg^(2-) and mat^(-) mixed ligands.The metal core of Ni_(10)cluster is a pudgy tetrahedron,whose four vertexes are four Ni^(2+)ions and the remanent six Ni^(2+) ions are located in the tetrahedral cavity.Four H_(3)thmmg^(2-) ligands are located at the four vertices of the tetrahedron and 8 mat^(-) ligands are all on the six sides of the tetrahedron.The different synthetic conditions contribute to the different configurations.Magnetic studies indicate that both complexes Ni_(8) and Ni_(10) display antiferromagnetic interactions.展开更多
Single-atom catalysts(SACs)have attracted increasing concerns in electrocatalysis because of their maximal metal atom utilization,distinctive electronic properties,and catalytic performance.However,the isolated single...Single-atom catalysts(SACs)have attracted increasing concerns in electrocatalysis because of their maximal metal atom utilization,distinctive electronic properties,and catalytic performance.However,the isolated single sites are disadvantageous for reactions that require simultaneously activating different reactants/intermediates.Fully exposed metal cluster catalyst(FECC),inheriting the merits of SACs and metallic nanoparticles,can synergistically adsorb and activate reactants/intermediates on their multi-atomic sites,demonstrating great promise in electrocatalytic reactions.Here a facile method to regulate the atomic dispersion of Ni species from cluster to single-atom scale for efficient CO_(2) reduction was developed.The obtained Ni FECC exhibits high Faradaic efficiency of CO up to 99%,high CO partial current density of 347.2 mA cm^(−2),and robust durability under 20 h electrolysis.Theoretical calculations illuminate that the ensemble of multiple Ni atoms regulated by sulfur atoms accelerates the reaction kinetics and thus improves CO production.展开更多
Two mononuclear metal-organic complexes, [Co（Hmpdc）2（H2O）4]·4H2O 1 and [Ni（Hfmpdc）2（H2O）4]·6H2O 2, were prepared from 2,6-dimethylpyridine-3,5-dicarboxylic acid （Hzmpdc） and 4-furyl-2,6-dimethylpyr...Two mononuclear metal-organic complexes, [Co（Hmpdc）2（H2O）4]·4H2O 1 and [Ni（Hfmpdc）2（H2O）4]·6H2O 2, were prepared from 2,6-dimethylpyridine-3,5-dicarboxylic acid （Hzmpdc） and 4-furyl-2,6-dimethylpyridine-3,5-dicarboxylic acid （H2fmpdc） with M（NO3）2 salts, respectively, and characterized by single-crystal X-ray diffraction, elemental analyses, IR spectroscopy, and photoluminescent measurement. Complex 1 crystallizes in triclinic, space group P1 with a = 7.634（5）, b = 8.695（5）, c = 10.757（6）A, α = 69.647（7）, β = 69.957（8）, γ = 83.733（7）°, V = 628.9（7）A^3, Dc = 1. 561 g/cm^3,μ（MoKa） = 0.763 mm^-1, F（000） = 309, Z = 1, the final R = 0.0553 and wR = 0.1469 for 1909 observed reflections （Ⅰ 〉 2σ（Ⅰ））. Complex 2 crystallizes in monoclinic, space group P21/n with a = 9.5934（16）, b = 12.422（2）, c = 14.826（3） A, β = 105.201（2）°, V = 1705.0（5）A3, Dc = 1. 479 g/cm^3,μ（MoKa） = 0.655 mm^-1, F（000） = 796, Z = 2, the final R= 0.0351 and wR = 0.0889 for 2387 obsevved reflections （Ⅰ 〉 2σ（Ⅰ））. In the crystal structures of 1 and 2, diverse supramolecular motifs from 1-D chains/ladders to 3-D networks are constructed from corresponding distinct [M^Ⅱ（H2O）8] ion clusters as the second building units, respectively. The solid state compounds of 1 and 2 show similar photoluminescent spectra with emission maximum at ca.展开更多
The possible geometrical and the electronic structures of small MgnNi （n = 1 - 7） clusters are optimised by the density functional theory with a LANL2DZ basis set. The binding energy, the energy gap, the electron af...The possible geometrical and the electronic structures of small MgnNi （n = 1 - 7） clusters are optimised by the density functional theory with a LANL2DZ basis set. The binding energy, the energy gap, the electron affinity, the dissociation energy and the second difference in energy are calculated and discussed. The properties of MgnNi clusters are also discussed when the number of Mg atom increases.展开更多
The lowest-energy structures and properties of neutral nickel clusters Nin（n=31―35） were studied by a combination method of genetic algorithm（GA） searching with a tight-binding potential and the density functiona...The lowest-energy structures and properties of neutral nickel clusters Nin（n=31―35） were studied by a combination method of genetic algorithm（GA） searching with a tight-binding potential and the density functional theory（DFT） calculations.Structural candidates obtained from our GA search were further optimized with first-principles calculations.Four typical isomers of lower-energy neutral Nin（n=31―35） clusters were shown,as well as their binding energies per atom（Eb）,second differences in energy and magnetic moment.The medium-sized nickel clusters in a size range from 31 atoms to 35 atoms were found to favor the distorted double-icosahedron-like structures.The fragments composed of the central atoms appear as some small stable clusters.展开更多
Two-dimensional metal dichalcogenides have been evidenced as potential electrocatalysts for hydrogen evolution reaction(HER);however,their application is limited by a poor oxygen evolution reaction(OER)activity due to...Two-dimensional metal dichalcogenides have been evidenced as potential electrocatalysts for hydrogen evolution reaction(HER);however,their application is limited by a poor oxygen evolution reaction(OER)activity due to insufficient number/types of multi-integrated active sites.In this study,we report a novel bifunctional catalyst developed by simultaneous engineering of single nickel atoms(Ni_(SA)) and nickel phosphate clusters(Ni_(Pi)) to synergistically trigger surface-functionalized MoS_(2) nanosheets(NSs)resulting in high reactivities for both HER and OER.The Ni_(SA)-Ni_(Pi)/MoS_(2)NSs material exhibits a fairly Pt-like HER behavior with an overpotential of 94.0 mV and a small OER overpotential of 314.0 mV to reach 10 mA cm^(-2) in freshwater containing 1.0 M KOH.Experimental results of the catalyst are well supported by theoretical study,which reveals the significant modulation of electronic structure and enrichment of electroactive site number/types with their reasonably adjusted free adsorption energy.For evaluating practicability,the Ni_(SA)-Ni_(Pi)/MoS_(2)NSs-based electrolyzer delivers effective operation voltage of 1.62,1.52,and 1.66 V at 10 mA cm^(-2) and superior long-term stability as compared to Pt/C//RuO_(2) system in freshwater,mimic seawater,and natural seawater,respectively.The present study indicates that the catalyst is a promising candidate for the practical production of green hydrogen via water electrolysis.展开更多
The title compound, [NiL]5[V34O82·8H2O （1, L=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane）, has been synthesized under hydrothermal conditions and structurally characterized by EA, IR, XPS, TG an...The title compound, [NiL]5[V34O82·8H2O （1, L=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane）, has been synthesized under hydrothermal conditions and structurally characterized by EA, IR, XPS, TG and single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group C2/c with a=33.061（4）, b=15.3457（17）, c=33.902（4）, β=101.930（2）°, Mr=4904.08, V=16828（3）3 , Z=4, Dc=1.936 g/cm3 , F（000）=9832, μ=2.425 mm-1 , the final R=0.0402 and wR=0.0969. The mixed valence vanadium clusters of [V34O82]10- bridges [NiL]2＋ to form a one-dimensional chain in 1. To the best of our knowledge, the title complex is the first example of organic-inorganic hybrid material involving the largest vanadium cluster of [V34O82]10-.展开更多
Based on spin-polarized density functional theory (DFT) calculations, the interaction between nickel cluster decorated single-wall carbon nanotube (CNT) and CO molecule has been investigated. DFT calculations are perf...Based on spin-polarized density functional theory (DFT) calculations, the interaction between nickel cluster decorated single-wall carbon nanotube (CNT) and CO molecule has been investigated. DFT calculations are performed with generalized gradient approximation (GGA) using Perdew-Burke-Ernzerhof (PBE) functional. Interaction of CNT and cluster induces spin polarization in the CNT. Nickel decorated CNT has a large magnetic moment of 4.00 μB which decreases to 0.10 μB when CO molecule is absorbed to it. Such a drastic reduction in magnetization may be detected by SQUID magnetometer. Hence by measuring magnetization change, CNT-cluster system may be used as gas detectors. The charge transfer between the systems has been discussed through Mulliken charge analysis for different orientations of the adsorbed CO molecule. We observed that CNT-cluster system acts as electron donor and CO molecule acts as electron acceptor in this study.展开更多
Under given conditions, two complexes of [Ni（H20）2BEDA]·2H2O 1 and [Ni（Py）2- BEDA]·6H2O 2 （BEDA = bis（3-methoxy-2-pyridyl）ether-6,6′-dicarboxylic acid） have been synthesized and characterized by ele...Under given conditions, two complexes of [Ni（H20）2BEDA]·2H2O 1 and [Ni（Py）2- BEDA]·6H2O 2 （BEDA = bis（3-methoxy-2-pyridyl）ether-6,6′-dicarboxylic acid） have been synthesized and characterized by elemental analysis and X-ray single-crystal diffraction. Crystal data for 1： C14H18NiN2O11, monoelinic C2/c, a = 14.3844（17）, b = 12.9900（15）, c = 9.6309（11） A, β = 104.3350（10）°, V= 1743.5（4） A3, Z = 4, Dc= 1.711 g/cm^3, F（000） = 928, μ = 1.179 mm^-1, Mr= 449.01, the final R = 0.0228 and wR = 0.0625. Crystal data for 2： C24H32NiN4O13, triclinic P1, a = 9.423（2）, b = 11.863（3）, c = 13.089（3） A, α = 91.511（3）, β = 92.465（3）, γ = 100.696（2）°, V = 1435.6（6） A^3, Z = 2, Dc= 1.488 g/cm^3, F（000） = 672, μ = 0.748 mm^-1, Mr= 643.25, the final R = 0.0400 and wR = 0.0975. Interestingly, in the two complexes, lattice water molecules dominate its crystal structures. Therefore, extensive intermolecular hydrogen bonds assemble 1 and 2 into 2D extended sheets and a 3D open framework, respectively. Furthermore, water molecules present in 2 are associated to form water clusters.展开更多
A nickel(Ⅱ) cluster,{[Ni(L)H2O]2(OAc)2Ni}.2EtOH,has been synthesized by the means of the complexation of nickel(Ⅱ) acetate tetrahydrate with a new Salen-type bisoxime ligand (H2L,4,4'-dimethoxy-2,2'-[ethylen...A nickel(Ⅱ) cluster,{[Ni(L)H2O]2(OAc)2Ni}.2EtOH,has been synthesized by the means of the complexation of nickel(Ⅱ) acetate tetrahydrate with a new Salen-type bisoxime ligand (H2L,4,4'-dimethoxy-2,2'-[ethylenedioxybis (nitrilo-methylidyne)]diphenol). The crystal structure shows that the hexacoodinated terminal nickel(Ⅱ) ions lie in the N2O2 coordination sphere of Salen-type bisoxime ligands,quadruple μ-phenoxo oxygen atoms from two [NiL] chelates coordinated to the central nickel(Ⅱ) ion,and the two acetate anions coordinated to three nickel(Ⅱ) ions through Ni-O-C-O-Ni bridges. Thus,all the three nickel atoms of the cluster have distorted octahedral geometries. CCDC:736762.展开更多
文摘This paper obtains the lowest-energy geometric structures and the electronic and magnetic properties of small CuNiN clusters by using all-electron density functional theory. The calculated results reveal that the Cu atom prefers to occupy the apical site when N ≤ 9 and for the clusters with N = 10, the Cu atom starts to encapsulate in the cage. The CuNi7 and CuNi9 are magic clusters. The magnetism correlates closely with the symmetry of the clusters. For these clusters, the charge tends to transfer from the nickel atoms to the copper atoms. It finds that the doping of Cu atom decreases the stability of pure NiN clusters.
基金financial support from the National Natural Science Foundation of China(Nos.22101148,22071126)the Natural Science Foundation of Shandong Province(No.ZR2021QB008)。
文摘Based on the reported Fe clusters constructed by using N-tris(hydroxymethyl)methylglycine (H_5thmmg),herein,we explored the use of H_5 thmmg for Ni chemistry.Successfully,an octanuclear Ni cluster,Ni_(8)O(H_(3)thmmg)_6·2NO_(3)(Ni_(8)) was acquired under solvothermal condition.Its metallic core is comprised of two centrosymmetric cubanes Ni_(4)(μ_(3)-O)_(3)(μ_6-O) linked by sharing an O^(2-)ion and six H_(3)thmmg^(2-) ligands are attached to the periphery.Interestingly,the 2-mercapto-5-amino-1,3,4-thiadiazole (Hmat) ligand with both N and S donor atoms was introduced into the synthesis of Ni_(8) cluster,a disparate decanuclear nickel cluster,Ni_(10)O(OH)_(2)(H_(3)thmmg)_(4)(mat)_(8)(Ni_(10)) is assembled by H_(3)thmmg^(2-) and mat^(-) mixed ligands.The metal core of Ni_(10)cluster is a pudgy tetrahedron,whose four vertexes are four Ni^(2+)ions and the remanent six Ni^(2+) ions are located in the tetrahedral cavity.Four H_(3)thmmg^(2-) ligands are located at the four vertices of the tetrahedron and 8 mat^(-) ligands are all on the six sides of the tetrahedron.The different synthetic conditions contribute to the different configurations.Magnetic studies indicate that both complexes Ni_(8) and Ni_(10) display antiferromagnetic interactions.
基金funding from the Alexander von Humboldt Foundation(Germany)supported by the National Key R&D Program of China(2020YFB1505603)+2 种基金the National Natural Science Foundation of China(51925102)Key Research Program of the Chinese Academy of Sciences(ZDRW-CN-2021-3)Youth Innovation Promotion Association CAS(E1202002)。
文摘Single-atom catalysts(SACs)have attracted increasing concerns in electrocatalysis because of their maximal metal atom utilization,distinctive electronic properties,and catalytic performance.However,the isolated single sites are disadvantageous for reactions that require simultaneously activating different reactants/intermediates.Fully exposed metal cluster catalyst(FECC),inheriting the merits of SACs and metallic nanoparticles,can synergistically adsorb and activate reactants/intermediates on their multi-atomic sites,demonstrating great promise in electrocatalytic reactions.Here a facile method to regulate the atomic dispersion of Ni species from cluster to single-atom scale for efficient CO_(2) reduction was developed.The obtained Ni FECC exhibits high Faradaic efficiency of CO up to 99%,high CO partial current density of 347.2 mA cm^(−2),and robust durability under 20 h electrolysis.Theoretical calculations illuminate that the ensemble of multiple Ni atoms regulated by sulfur atoms accelerates the reaction kinetics and thus improves CO production.
基金supported by the NNSFC (No. 20701041)the Key Project of Chinese Ministry of Education (No. 208116)+1 种基金the Natural Science Foundation of CQ CSTC (No. 2007BB5228)the Scientific and Technological Project of CQEC (No. KJ080829).
文摘Two mononuclear metal-organic complexes, [Co（Hmpdc）2（H2O）4]·4H2O 1 and [Ni（Hfmpdc）2（H2O）4]·6H2O 2, were prepared from 2,6-dimethylpyridine-3,5-dicarboxylic acid （Hzmpdc） and 4-furyl-2,6-dimethylpyridine-3,5-dicarboxylic acid （H2fmpdc） with M（NO3）2 salts, respectively, and characterized by single-crystal X-ray diffraction, elemental analyses, IR spectroscopy, and photoluminescent measurement. Complex 1 crystallizes in triclinic, space group P1 with a = 7.634（5）, b = 8.695（5）, c = 10.757（6）A, α = 69.647（7）, β = 69.957（8）, γ = 83.733（7）°, V = 628.9（7）A^3, Dc = 1. 561 g/cm^3,μ（MoKa） = 0.763 mm^-1, F（000） = 309, Z = 1, the final R = 0.0553 and wR = 0.1469 for 1909 observed reflections （Ⅰ 〉 2σ（Ⅰ））. Complex 2 crystallizes in monoclinic, space group P21/n with a = 9.5934（16）, b = 12.422（2）, c = 14.826（3） A, β = 105.201（2）°, V = 1705.0（5）A3, Dc = 1. 479 g/cm^3,μ（MoKa） = 0.655 mm^-1, F（000） = 796, Z = 2, the final R= 0.0351 and wR = 0.0889 for 2387 obsevved reflections （Ⅰ 〉 2σ（Ⅰ））. In the crystal structures of 1 and 2, diverse supramolecular motifs from 1-D chains/ladders to 3-D networks are constructed from corresponding distinct [M^Ⅱ（H2O）8] ion clusters as the second building units, respectively. The solid state compounds of 1 and 2 show similar photoluminescent spectra with emission maximum at ca.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10676022)
文摘The possible geometrical and the electronic structures of small MgnNi （n = 1 - 7） clusters are optimised by the density functional theory with a LANL2DZ basis set. The binding energy, the energy gap, the electron affinity, the dissociation energy and the second difference in energy are calculated and discussed. The properties of MgnNi clusters are also discussed when the number of Mg atom increases.
基金Supported by the National Natural Science Foundation of China(Nos.21043001 and 20773047)
文摘The lowest-energy structures and properties of neutral nickel clusters Nin（n=31―35） were studied by a combination method of genetic algorithm（GA） searching with a tight-binding potential and the density functional theory（DFT） calculations.Structural candidates obtained from our GA search were further optimized with first-principles calculations.Four typical isomers of lower-energy neutral Nin（n=31―35） clusters were shown,as well as their binding energies per atom（Eb）,second differences in energy and magnetic moment.The medium-sized nickel clusters in a size range from 31 atoms to 35 atoms were found to favor the distorted double-icosahedron-like structures.The fragments composed of the central atoms appear as some small stable clusters.
基金supported by the Regional Leading Research Center Program(2019R1A5A8080326)Basic Science Research Program(2020R1F1A1075921)BRL Program(2020R1A4A1018259)through the National Research Foundation(NRF)funded by the Ministry of Science and ICT of Republic of Korea.
文摘Two-dimensional metal dichalcogenides have been evidenced as potential electrocatalysts for hydrogen evolution reaction(HER);however,their application is limited by a poor oxygen evolution reaction(OER)activity due to insufficient number/types of multi-integrated active sites.In this study,we report a novel bifunctional catalyst developed by simultaneous engineering of single nickel atoms(Ni_(SA)) and nickel phosphate clusters(Ni_(Pi)) to synergistically trigger surface-functionalized MoS_(2) nanosheets(NSs)resulting in high reactivities for both HER and OER.The Ni_(SA)-Ni_(Pi)/MoS_(2)NSs material exhibits a fairly Pt-like HER behavior with an overpotential of 94.0 mV and a small OER overpotential of 314.0 mV to reach 10 mA cm^(-2) in freshwater containing 1.0 M KOH.Experimental results of the catalyst are well supported by theoretical study,which reveals the significant modulation of electronic structure and enrichment of electroactive site number/types with their reasonably adjusted free adsorption energy.For evaluating practicability,the Ni_(SA)-Ni_(Pi)/MoS_(2)NSs-based electrolyzer delivers effective operation voltage of 1.62,1.52,and 1.66 V at 10 mA cm^(-2) and superior long-term stability as compared to Pt/C//RuO_(2) system in freshwater,mimic seawater,and natural seawater,respectively.The present study indicates that the catalyst is a promising candidate for the practical production of green hydrogen via water electrolysis.
基金supported by the Science and Technology Planning Project of Hunan Province (2012FJ3050, 2012NK3067)the Construct Program of the Key Discipline in Hunan Province (2011–76)the Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province (2012–318)
文摘The title compound, [NiL]5[V34O82·8H2O （1, L=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane）, has been synthesized under hydrothermal conditions and structurally characterized by EA, IR, XPS, TG and single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group C2/c with a=33.061（4）, b=15.3457（17）, c=33.902（4）, β=101.930（2）°, Mr=4904.08, V=16828（3）3 , Z=4, Dc=1.936 g/cm3 , F（000）=9832, μ=2.425 mm-1 , the final R=0.0402 and wR=0.0969. The mixed valence vanadium clusters of [V34O82]10- bridges [NiL]2＋ to form a one-dimensional chain in 1. To the best of our knowledge, the title complex is the first example of organic-inorganic hybrid material involving the largest vanadium cluster of [V34O82]10-.
文摘Based on spin-polarized density functional theory (DFT) calculations, the interaction between nickel cluster decorated single-wall carbon nanotube (CNT) and CO molecule has been investigated. DFT calculations are performed with generalized gradient approximation (GGA) using Perdew-Burke-Ernzerhof (PBE) functional. Interaction of CNT and cluster induces spin polarization in the CNT. Nickel decorated CNT has a large magnetic moment of 4.00 μB which decreases to 0.10 μB when CO molecule is absorbed to it. Such a drastic reduction in magnetization may be detected by SQUID magnetometer. Hence by measuring magnetization change, CNT-cluster system may be used as gas detectors. The charge transfer between the systems has been discussed through Mulliken charge analysis for different orientations of the adsorbed CO molecule. We observed that CNT-cluster system acts as electron donor and CO molecule acts as electron acceptor in this study.
基金supported by the Henan Innovation Project for University Prominent Research Talents (No. 2005KYCX021)Natural Science Foundation of Henan Province (No. 082300420040)
文摘Under given conditions, two complexes of [Ni（H20）2BEDA]·2H2O 1 and [Ni（Py）2- BEDA]·6H2O 2 （BEDA = bis（3-methoxy-2-pyridyl）ether-6,6′-dicarboxylic acid） have been synthesized and characterized by elemental analysis and X-ray single-crystal diffraction. Crystal data for 1： C14H18NiN2O11, monoelinic C2/c, a = 14.3844（17）, b = 12.9900（15）, c = 9.6309（11） A, β = 104.3350（10）°, V= 1743.5（4） A3, Z = 4, Dc= 1.711 g/cm^3, F（000） = 928, μ = 1.179 mm^-1, Mr= 449.01, the final R = 0.0228 and wR = 0.0625. Crystal data for 2： C24H32NiN4O13, triclinic P1, a = 9.423（2）, b = 11.863（3）, c = 13.089（3） A, α = 91.511（3）, β = 92.465（3）, γ = 100.696（2）°, V = 1435.6（6） A^3, Z = 2, Dc= 1.488 g/cm^3, F（000） = 672, μ = 0.748 mm^-1, Mr= 643.25, the final R = 0.0400 and wR = 0.0975. Interestingly, in the two complexes, lattice water molecules dominate its crystal structures. Therefore, extensive intermolecular hydrogen bonds assemble 1 and 2 into 2D extended sheets and a 3D open framework, respectively. Furthermore, water molecules present in 2 are associated to form water clusters.
文摘A nickel(Ⅱ) cluster,{[Ni(L)H2O]2(OAc)2Ni}.2EtOH,has been synthesized by the means of the complexation of nickel(Ⅱ) acetate tetrahydrate with a new Salen-type bisoxime ligand (H2L,4,4'-dimethoxy-2,2'-[ethylenedioxybis (nitrilo-methylidyne)]diphenol). The crystal structure shows that the hexacoodinated terminal nickel(Ⅱ) ions lie in the N2O2 coordination sphere of Salen-type bisoxime ligands,quadruple μ-phenoxo oxygen atoms from two [NiL] chelates coordinated to the central nickel(Ⅱ) ion,and the two acetate anions coordinated to three nickel(Ⅱ) ions through Ni-O-C-O-Ni bridges. Thus,all the three nickel atoms of the cluster have distorted octahedral geometries. CCDC:736762.
