Exploring highly active and stable transition metal-based bifunctional electrocatalysts has recently attracted extensive research interests for achieving high inherent activity, abundant exposed active sites, rapid ma...Exploring highly active and stable transition metal-based bifunctional electrocatalysts has recently attracted extensive research interests for achieving high inherent activity, abundant exposed active sites, rapid mass transfer, and strong structure stability for overall water splitting. Herein, an interface engineering coupled with shell-protection strategy was applied to construct three-dimensional(3D) core-shell NixSy@MnOxHy heterostructure nanorods grown on nickel foam(NixSy@MnOxHy/NF) as a bifunctional electrocatalyst. NixSy@MnOxHy/NF was synthesized via a facile hydrothermal reaction followed by an electrodeposition process. The X-ray absorption fine structure spectra reveal that abundant Mn-S bonds connect the heterostructure interfaces of N ixSy@MnOxHy, leading to a strong electronic interaction, which improves the intrinsic activities of hydrogen evolution reaction and oxygen evolution reaction(OER). Besides, as an efficient protective shell, the MnOxHy dramatically inhibits the electrochemical corrosion of the electrocatalyst at high current densities, which remarkably enhances the stability at high potentials. Furthermore, the 3D nanorod structure not only exposes enriched active sites, but also accelerates the electrolyte diffusion and bubble desorption. Therefore, NixSy@MnOxHy/NF exhibits exceptional bifunctional activity and stability for overall water splitting, with low overpotentials of 326 and 356 mV for OER at 100 and 500 mA cm^(–2), respectively, along with high stability of 150 h at 100 mA cm^(–2). Furthermore, for overall water splitting, it presents a low cell voltage of 1.529 V at 10 mA cm^(–2), accompanied by excellent stability at 100 mA cm^(–2) for 100 h. This work sheds a light on exploring highly active and stable bifunctional electrocatalysts by the interface engineering coupled with shell-protection strategy.展开更多
By use of a new ligand containing both salicylic acid moiety and salicylaldehyde Schiff base moiety, 5-(2-hydroxybenzylideneamino)-2-hydroxybenzoic acid (H3L), a linear trinuclear Mn(II) complex was prepared. Th...By use of a new ligand containing both salicylic acid moiety and salicylaldehyde Schiff base moiety, 5-(2-hydroxybenzylideneamino)-2-hydroxybenzoic acid (H3L), a linear trinuclear Mn(II) complex was prepared. This complex crystallizes in triclinic, space group P1 with a = 12.0196(7), b = 13.7440(13), c = 15.7554(14) , α = 111.529(3), β = 96.691(2), γ = 94.802(2)o, C96H100Mn3N6O32, Mr = 2014.64, V = 2382.0(3) 3, Z = 1, μ = 0.478, Dc = 1.404 g/cm3, F(000) = 1049, R = 0.0554 and wR = 0.1610 for 8973 observed reflections (I 〉 2σ(I)). The complex consists of a trinuclear cluster and two solvate ethanol molecules. Three linearly disposed Mn atoms, with an inversion center on the central one, are bridged by six carboxylate groups from six bulky mono-anionic ligands (H2L-), and the octahedral coordination spheres for each of the metal centers are thus formed, with the aid of additional ligation of two small molecules (ethanol and water) to both ends. The magnetic properties of the title complex are also included in this paper.展开更多
0D dinuclear manganese(Ⅱ)coordination compound and 1D chain manganese(Ⅱ)coordination polymer,namely[Mn2(μ-L)(phen)4]·4H2O(1)and{[Mn2(μ5-L)(phen)2]·H2O}n(2),have been constructed hydrothermally using H4L(...0D dinuclear manganese(Ⅱ)coordination compound and 1D chain manganese(Ⅱ)coordination polymer,namely[Mn2(μ-L)(phen)4]·4H2O(1)and{[Mn2(μ5-L)(phen)2]·H2O}n(2),have been constructed hydrothermally using H4L(H4L=2,3,3΄,4΄-diphenyl ether tetracarboxylic acid),phen(phen=1,10-phenanthroline),and manganese chloride at 120 and 160°C,respectively.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses(TGA),and single-crystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that two compounds crystallize in the triclinic or monoclinic system,space group P1 or P21/c.Compound 1 discloses a discrete dimeric structure,which is assembled into a 3D supramolecular framework through O-H…O hydrogen bond.Compound 2 has a chain structure.Structural differences between compounds 1 and 2 are attributed to the different reaction temperature.Magnetic studies for compound 2 demonstrate an antiferromagnetic coupling between the adjacent Mn(Ⅱ)centers.展开更多
The cryptomelane-type manganese oxide (OMS-2)-supported Co (x Co/OMS-2;x=5,10,and15 wt.%) catalysts were prepared via a pre-incorporation route.The as-prepared materials were used as catalysts for catalytic oxidation ...The cryptomelane-type manganese oxide (OMS-2)-supported Co (x Co/OMS-2;x=5,10,and15 wt.%) catalysts were prepared via a pre-incorporation route.The as-prepared materials were used as catalysts for catalytic oxidation of toluene (2000 ppmV).Physical and chemical properties of the catalysts were measured using the X-ray diffraction (XRD),Fourier transform infrared spectroscopic (FT-IR),scanning electron microscopic (SEM),X-ray photoelectron spectroscopy (XPS),and hydrogen temperature-programmed reduction (H_(2)-TPR)techniques.Among all of the catalysts,10Co/OMS-2 performed the best,with the T90%,specific reaction rate at 245℃,and turnover frequency at 245℃ (TOFCo) being 245℃,1.23×10^(-3)moltoluene/(gcat·sec),and 11.58×10^(-3)sec-1for toluene oxidation at a space velocity of 60,000mL/(g·hr),respectively.The excellent catalytic performance of 10Co/OMS-2 were due to more oxygen vacancies,enhanced redox ability and oxygen mobility,and strong synergistic effect between Co species and OMS-2 support.Moreover,in the presence of poisoning gases CO_(2),SO_(2)or NH_(3),the activity of 10Co/OMS-2 decreased for the carbonate,sulfate and ammonia species covered the active sites and oxygen vacancies,respectively.After the activation treatment,the catalytic activity was partly recovered.The good low-temperature reducibility of 10Co/OMS-2 could also facilitate the redox process accompanied by the consecutive electron transfer between the adsorbed O_(2)and the cobalt or manganese ions.In the oxidation process of toluene,the benzoic and aldehydic intermediates werefirst generated,which were further oxidized to the benzoate intermediate that were eventually converted into H_(2)O and CO_(2).展开更多
Comprehensive utilization of low grade manganese?zinc compound ore containing lead and silver with a method of reductive acid leaching was studied.According to theφ?pH diagram of Mn?Zn?H2O system,Mn and Zn can be lea...Comprehensive utilization of low grade manganese?zinc compound ore containing lead and silver with a method of reductive acid leaching was studied.According to theφ?pH diagram of Mn?Zn?H2O system,Mn and Zn can be leached simultaneously in the pH range of?2to5.61.The results showed that both hydrogen peroxide and sucrose were effective reductants which could intensify the simultaneous leaching of Mn and Zn into leachate as well as enrich Pb and Ag in the residue.95.88%of Mn and99.23%of Zn were extracted when the compound ore was leached with hydrogen peroxide in sulfuric acid media,meanwhile the contents of Pb and Ag in the residue were enriched to13.21%and489.36g/t,respectively.When sucrose was used as the reductant,the leaching efficiencies of Mn and Zn separately achieved98.26%and99.62%,and contents of Pb and Ag in the residue were as high as13.92%and517.87g/t,respectively.展开更多
A novel inclusion compound of [Mn(dca)2(3-nic)2]n·(3-nic)2n(1,dca = dicyanamide,3-nic = nicotinamide) has been prepared and characterized by single-crystal X-ray diffraction,elemental analysis and IR.This...A novel inclusion compound of [Mn(dca)2(3-nic)2]n·(3-nic)2n(1,dca = dicyanamide,3-nic = nicotinamide) has been prepared and characterized by single-crystal X-ray diffraction,elemental analysis and IR.This complex crystallizes in the triclinic system,space group P1 with a = 7.5979(8),b = 7.7128(9),c = 14.5346(17),α = 100.094(2),β = 92.444(2),γ = 116.736(2)o,V = 741.72(15) 3,Z = 1,Dc = 1.512 g/cm3,Mr = 675.55,μ = 0.507 mm-1,F(000) = 347,S = 1.023,the final R = 0.0400 and wR = 0.1010.The inclusion compound is constructed by a three-dimensional host network that consists of dca,3-nic and Mn2+ with coordination and hydrogen-bonding interactions.In the network,one-dimensional rectangular channels are formed,and the guest molecules(3-nic) are included in the channels.The guest molecules interlink with the host through strong hydrogen bonds.展开更多
The title compound, [Mn(salen)(salicyl)]?.5H2O ( H2salen = N, N?ethylenebis- (salicylideneaminato), Hsalicyl = salicylaldehyde), has been obtained from the reaction system containing (o-HOC6H4CH=NCH2)2, o-HOC6H4CHO an...The title compound, [Mn(salen)(salicyl)]?.5H2O ( H2salen = N, N?ethylenebis- (salicylideneaminato), Hsalicyl = salicylaldehyde), has been obtained from the reaction system containing (o-HOC6H4CH=NCH2)2, o-HOC6H4CHO and Mn(ClO4)2?H2O in EtOH solvent and structurally characterized. It crystallizes in the monoclinic, space group P21/c with a = 13.0548(4), b = 13.9254(4), c = 11.6630(1) ? b = 105.199(2)? V = 2046.09(9) ?, Z = 4, C23H22MnN2O5.5, Mr = 469.37, Dc = 1.524 g/cm3, F(000) = 972, m = 0.687mm-1 . R = 0.0630 and wR = 0.1142 for 1901 observed reflections with I >2(I). The Mn(Ⅲ) is coordinated by N(1), N(2), O(1) and O(2) of the Schiff base ligand and phenolate O atom of salicylaldehyde with O(3)Mn distance of 2.050(4) , forming a relatively rare five-coordinate square-pyramidal structure.展开更多
A new four-coordinated manganese compound Mn2(BPTC) (BPTC =- biphenyl- 2,4,4',6-tetracarboxylate) with flu topology net was synthesized under hydrothermal conditions. Single-crystal X-ray diffraction analysis con...A new four-coordinated manganese compound Mn2(BPTC) (BPTC =- biphenyl- 2,4,4',6-tetracarboxylate) with flu topology net was synthesized under hydrothermal conditions. Single-crystal X-ray diffraction analysis confirms its crystal belongs to the monoclinic system, space group C2/c with a = 12.2092(11), b = 14.6932(9), c = 8.9998(10) A, t= 108.256(12)°, Z= 4, V= 1533.2(2) A3, Dc = 1.889 mg/m3,μ = 1.69, F(O00) = 864, the final R = 0.063 and wR = 0.201 for 1407 observed reflections (I 〉 20(/)). UV-Vis absorption spectrum shows the title compound has a strong absorption at 326 and 238 nm and the optical diffuse reflectance determination shows the band gap of the title compound is 3.15 eV. The theory calculation elucidated that the UV absorptions of the title compound mainly arise from the electron transition from bonding orbitals of BPTC4- ligand to the empty orbitals of BPTC4- and Mn(II) ions.展开更多
The title compound of o-vanillin ethylene diamine Schiff base monoacetic acid manganese(Ⅱ) monohydrate, Mn((CH3 OC6 H3 OCHNC2H4NCHC6H3OO-CH3) (H2O) (CH3COOH). CH3OH. 2H2O, was synthesized and its crystal structurewas...The title compound of o-vanillin ethylene diamine Schiff base monoacetic acid manganese(Ⅱ) monohydrate, Mn((CH3 OC6 H3 OCHNC2H4NCHC6H3OO-CH3) (H2O) (CH3COOH). CH3OH. 2H2O, was synthesized and its crystal structurewas determined by X-ray diffraction methed. Crystal data are: Mr = 527. 43, monoclinic system, space group C2/c, Z= 8 F a= 17. 720(4), b= 12. 584(3), c= 22. 648(5)A, β= 112. 61 (3)°; V=4662(4) A, Dx=1. 503 g/cm3, μ=5. 99 cm-1, F(000) =2216. The final agreement factors are R= 0. 053 and Rw= 0. 056 for 2208 unique refiections (I>3σ(I) )- The manganese(Ⅱ) is coordinated to N(1), N (2), O(2) ) O(3) of Schiff base ligand, O atom of water and O(11) of acetic acid. They formed adistorted octahedral structure. Each asymmetry contains one solvent methanol moleculeand two solvent water molecules.展开更多
A new manganese compound [Mn8(tmp)2(Htmp)4((CH3)3CCO2)4(py)2Cl2]·2py (1·2py, H3tmp = 1,1,1-tri(hydroxymethyl)propane, py = pyramid) has been synthesized and its structure was characterized by I...A new manganese compound [Mn8(tmp)2(Htmp)4((CH3)3CCO2)4(py)2Cl2]·2py (1·2py, H3tmp = 1,1,1-tri(hydroxymethyl)propane, py = pyramid) has been synthesized and its structure was characterized by IR, elemental analysis and X-ray diffraction. Compound 1 belongs to the triclinic system, space group P1 with a = 13.378(5), b = 14.334(5), c = 15.012(6) , α = 107.637(5), β = 95.635(3), γ = 92.825(4)°, V = 2720.7(17) 3, Z = 1, C76H124N4O26Cl2Mn8, Mr = 2022.23, Dc = 1.234 Mg/m3, μ = 1.007 mm-1, F(000) = 1052, T = 293(2) K, the final R = 0.0755 and wR = 0.2163 for all 6463 observed reflections (I 〉 2σ(I)). X-ray analysis shows that the core of 1 contains a [Mn8] mixed-valence rod-like unit consisting of six edge-sharing triangles (Mn3), each of which is bridged by a μ3-oxygen atom.展开更多
基金supported by the Guangdong Basic and Applied Basic Research Foundation(2021A1515110859)the Research Fund Program of Key Laboratory of Fuel Cell Technology of Guangdong Province+2 种基金the Natural Sciences and Engineering Research Council of Canada(NSERC)Institut National de la Recherche Scientifique(INRS)。
文摘Exploring highly active and stable transition metal-based bifunctional electrocatalysts has recently attracted extensive research interests for achieving high inherent activity, abundant exposed active sites, rapid mass transfer, and strong structure stability for overall water splitting. Herein, an interface engineering coupled with shell-protection strategy was applied to construct three-dimensional(3D) core-shell NixSy@MnOxHy heterostructure nanorods grown on nickel foam(NixSy@MnOxHy/NF) as a bifunctional electrocatalyst. NixSy@MnOxHy/NF was synthesized via a facile hydrothermal reaction followed by an electrodeposition process. The X-ray absorption fine structure spectra reveal that abundant Mn-S bonds connect the heterostructure interfaces of N ixSy@MnOxHy, leading to a strong electronic interaction, which improves the intrinsic activities of hydrogen evolution reaction and oxygen evolution reaction(OER). Besides, as an efficient protective shell, the MnOxHy dramatically inhibits the electrochemical corrosion of the electrocatalyst at high current densities, which remarkably enhances the stability at high potentials. Furthermore, the 3D nanorod structure not only exposes enriched active sites, but also accelerates the electrolyte diffusion and bubble desorption. Therefore, NixSy@MnOxHy/NF exhibits exceptional bifunctional activity and stability for overall water splitting, with low overpotentials of 326 and 356 mV for OER at 100 and 500 mA cm^(–2), respectively, along with high stability of 150 h at 100 mA cm^(–2). Furthermore, for overall water splitting, it presents a low cell voltage of 1.529 V at 10 mA cm^(–2), accompanied by excellent stability at 100 mA cm^(–2) for 100 h. This work sheds a light on exploring highly active and stable bifunctional electrocatalysts by the interface engineering coupled with shell-protection strategy.
基金supported by the NNSFC (Nos. 20633020 and 20973172)the 973 Program (No. 2009CB220009)the NSF of Fujian Province (Nos. 2008J0175 and 2007F3112)
文摘By use of a new ligand containing both salicylic acid moiety and salicylaldehyde Schiff base moiety, 5-(2-hydroxybenzylideneamino)-2-hydroxybenzoic acid (H3L), a linear trinuclear Mn(II) complex was prepared. This complex crystallizes in triclinic, space group P1 with a = 12.0196(7), b = 13.7440(13), c = 15.7554(14) , α = 111.529(3), β = 96.691(2), γ = 94.802(2)o, C96H100Mn3N6O32, Mr = 2014.64, V = 2382.0(3) 3, Z = 1, μ = 0.478, Dc = 1.404 g/cm3, F(000) = 1049, R = 0.0554 and wR = 0.1610 for 8973 observed reflections (I 〉 2σ(I)). The complex consists of a trinuclear cluster and two solvate ethanol molecules. Three linearly disposed Mn atoms, with an inversion center on the central one, are bridged by six carboxylate groups from six bulky mono-anionic ligands (H2L-), and the octahedral coordination spheres for each of the metal centers are thus formed, with the aid of additional ligation of two small molecules (ethanol and water) to both ends. The magnetic properties of the title complex are also included in this paper.
基金supported by Guangdong Province Higher Vocational Colleges&Schools Pearl River Scholar Funded Scheme(2015,2018)the Natural Science Foundation of Guangdong Province(No.2016A030313761)+3 种基金the Pearl River Scholar Foundation of Guangdong Industry Polytechnic(RC2015-001)the Opening Foundation of MOE Key Laboratory of MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of Chemistry Sun Yat-Sen University(2016)Innovation Team Project on University of Guangdong Province(2017GKCXTD001)Science and Technology Planning Project of Guangzhou(201904010381)the Science and Technology Plan of Qinghai Province(2018-ZJ-919)。
文摘0D dinuclear manganese(Ⅱ)coordination compound and 1D chain manganese(Ⅱ)coordination polymer,namely[Mn2(μ-L)(phen)4]·4H2O(1)and{[Mn2(μ5-L)(phen)2]·H2O}n(2),have been constructed hydrothermally using H4L(H4L=2,3,3΄,4΄-diphenyl ether tetracarboxylic acid),phen(phen=1,10-phenanthroline),and manganese chloride at 120 and 160°C,respectively.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses(TGA),and single-crystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that two compounds crystallize in the triclinic or monoclinic system,space group P1 or P21/c.Compound 1 discloses a discrete dimeric structure,which is assembled into a 3D supramolecular framework through O-H…O hydrogen bond.Compound 2 has a chain structure.Structural differences between compounds 1 and 2 are attributed to the different reaction temperature.Magnetic studies for compound 2 demonstrate an antiferromagnetic coupling between the adjacent Mn(Ⅱ)centers.
基金supported by the National Natural Science Foundation of China (Nos. 21277008 and 20777005)National Key Research and Development Program of China (No. 2017YFC0209905)。
文摘The cryptomelane-type manganese oxide (OMS-2)-supported Co (x Co/OMS-2;x=5,10,and15 wt.%) catalysts were prepared via a pre-incorporation route.The as-prepared materials were used as catalysts for catalytic oxidation of toluene (2000 ppmV).Physical and chemical properties of the catalysts were measured using the X-ray diffraction (XRD),Fourier transform infrared spectroscopic (FT-IR),scanning electron microscopic (SEM),X-ray photoelectron spectroscopy (XPS),and hydrogen temperature-programmed reduction (H_(2)-TPR)techniques.Among all of the catalysts,10Co/OMS-2 performed the best,with the T90%,specific reaction rate at 245℃,and turnover frequency at 245℃ (TOFCo) being 245℃,1.23×10^(-3)moltoluene/(gcat·sec),and 11.58×10^(-3)sec-1for toluene oxidation at a space velocity of 60,000mL/(g·hr),respectively.The excellent catalytic performance of 10Co/OMS-2 were due to more oxygen vacancies,enhanced redox ability and oxygen mobility,and strong synergistic effect between Co species and OMS-2 support.Moreover,in the presence of poisoning gases CO_(2),SO_(2)or NH_(3),the activity of 10Co/OMS-2 decreased for the carbonate,sulfate and ammonia species covered the active sites and oxygen vacancies,respectively.After the activation treatment,the catalytic activity was partly recovered.The good low-temperature reducibility of 10Co/OMS-2 could also facilitate the redox process accompanied by the consecutive electron transfer between the adsorbed O_(2)and the cobalt or manganese ions.In the oxidation process of toluene,the benzoic and aldehydic intermediates werefirst generated,which were further oxidized to the benzoate intermediate that were eventually converted into H_(2)O and CO_(2).
基金Projects(51574284,51504293)supported by the National Natural Science Foundation of ChinaProject(2013IB020)supported by the Science and Technology Program of Yunnan Province,ChinaProject(CSUZC201606)supported by the Open-End Fund for the Valuable and Precision Instruments of Central South University,China
文摘Comprehensive utilization of low grade manganese?zinc compound ore containing lead and silver with a method of reductive acid leaching was studied.According to theφ?pH diagram of Mn?Zn?H2O system,Mn and Zn can be leached simultaneously in the pH range of?2to5.61.The results showed that both hydrogen peroxide and sucrose were effective reductants which could intensify the simultaneous leaching of Mn and Zn into leachate as well as enrich Pb and Ag in the residue.95.88%of Mn and99.23%of Zn were extracted when the compound ore was leached with hydrogen peroxide in sulfuric acid media,meanwhile the contents of Pb and Ag in the residue were enriched to13.21%and489.36g/t,respectively.When sucrose was used as the reductant,the leaching efficiencies of Mn and Zn separately achieved98.26%and99.62%,and contents of Pb and Ag in the residue were as high as13.92%and517.87g/t,respectively.
基金Supported by the project of Scientific Research Foundation for Talent Introduction of Chongqing university (No. 0903005104728)
文摘A novel inclusion compound of [Mn(dca)2(3-nic)2]n·(3-nic)2n(1,dca = dicyanamide,3-nic = nicotinamide) has been prepared and characterized by single-crystal X-ray diffraction,elemental analysis and IR.This complex crystallizes in the triclinic system,space group P1 with a = 7.5979(8),b = 7.7128(9),c = 14.5346(17),α = 100.094(2),β = 92.444(2),γ = 116.736(2)o,V = 741.72(15) 3,Z = 1,Dc = 1.512 g/cm3,Mr = 675.55,μ = 0.507 mm-1,F(000) = 347,S = 1.023,the final R = 0.0400 and wR = 0.1010.The inclusion compound is constructed by a three-dimensional host network that consists of dca,3-nic and Mn2+ with coordination and hydrogen-bonding interactions.In the network,one-dimensional rectangular channels are formed,and the guest molecules(3-nic) are included in the channels.The guest molecules interlink with the host through strong hydrogen bonds.
基金This work was supported by the State Key Basic Research and Development Plan (G1998010100) NNSFC (No. 29733090 and 29973047)
文摘The title compound, [Mn(salen)(salicyl)]?.5H2O ( H2salen = N, N?ethylenebis- (salicylideneaminato), Hsalicyl = salicylaldehyde), has been obtained from the reaction system containing (o-HOC6H4CH=NCH2)2, o-HOC6H4CHO and Mn(ClO4)2?H2O in EtOH solvent and structurally characterized. It crystallizes in the monoclinic, space group P21/c with a = 13.0548(4), b = 13.9254(4), c = 11.6630(1) ? b = 105.199(2)? V = 2046.09(9) ?, Z = 4, C23H22MnN2O5.5, Mr = 469.37, Dc = 1.524 g/cm3, F(000) = 972, m = 0.687mm-1 . R = 0.0630 and wR = 0.1142 for 1901 observed reflections with I >2(I). The Mn(Ⅲ) is coordinated by N(1), N(2), O(1) and O(2) of the Schiff base ligand and phenolate O atom of salicylaldehyde with O(3)Mn distance of 2.050(4) , forming a relatively rare five-coordinate square-pyramidal structure.
基金supported by the Natural Science Foundation of Fujian Province(No.2014J01029)the National Natural Science Foundation of China(No.91122028)
文摘A new four-coordinated manganese compound Mn2(BPTC) (BPTC =- biphenyl- 2,4,4',6-tetracarboxylate) with flu topology net was synthesized under hydrothermal conditions. Single-crystal X-ray diffraction analysis confirms its crystal belongs to the monoclinic system, space group C2/c with a = 12.2092(11), b = 14.6932(9), c = 8.9998(10) A, t= 108.256(12)°, Z= 4, V= 1533.2(2) A3, Dc = 1.889 mg/m3,μ = 1.69, F(O00) = 864, the final R = 0.063 and wR = 0.201 for 1407 observed reflections (I 〉 20(/)). UV-Vis absorption spectrum shows the title compound has a strong absorption at 326 and 238 nm and the optical diffuse reflectance determination shows the band gap of the title compound is 3.15 eV. The theory calculation elucidated that the UV absorptions of the title compound mainly arise from the electron transition from bonding orbitals of BPTC4- ligand to the empty orbitals of BPTC4- and Mn(II) ions.
文摘The title compound of o-vanillin ethylene diamine Schiff base monoacetic acid manganese(Ⅱ) monohydrate, Mn((CH3 OC6 H3 OCHNC2H4NCHC6H3OO-CH3) (H2O) (CH3COOH). CH3OH. 2H2O, was synthesized and its crystal structurewas determined by X-ray diffraction methed. Crystal data are: Mr = 527. 43, monoclinic system, space group C2/c, Z= 8 F a= 17. 720(4), b= 12. 584(3), c= 22. 648(5)A, β= 112. 61 (3)°; V=4662(4) A, Dx=1. 503 g/cm3, μ=5. 99 cm-1, F(000) =2216. The final agreement factors are R= 0. 053 and Rw= 0. 056 for 2208 unique refiections (I>3σ(I) )- The manganese(Ⅱ) is coordinated to N(1), N (2), O(2) ) O(3) of Schiff base ligand, O atom of water and O(11) of acetic acid. They formed adistorted octahedral structure. Each asymmetry contains one solvent methanol moleculeand two solvent water molecules.
基金Supported by the National Natural Science Foundation of China (Nos. 20633020 and 20973172)the National Basic Research Program of China (No. 2009CB220009)+1 种基金the Natural Science Foundation of Fujian Province (No. 2008J0175)the Fujian Province Youth Foundation (No. 2007F3112)
文摘A new manganese compound [Mn8(tmp)2(Htmp)4((CH3)3CCO2)4(py)2Cl2]·2py (1·2py, H3tmp = 1,1,1-tri(hydroxymethyl)propane, py = pyramid) has been synthesized and its structure was characterized by IR, elemental analysis and X-ray diffraction. Compound 1 belongs to the triclinic system, space group P1 with a = 13.378(5), b = 14.334(5), c = 15.012(6) , α = 107.637(5), β = 95.635(3), γ = 92.825(4)°, V = 2720.7(17) 3, Z = 1, C76H124N4O26Cl2Mn8, Mr = 2022.23, Dc = 1.234 Mg/m3, μ = 1.007 mm-1, F(000) = 1052, T = 293(2) K, the final R = 0.0755 and wR = 0.2163 for all 6463 observed reflections (I 〉 2σ(I)). X-ray analysis shows that the core of 1 contains a [Mn8] mixed-valence rod-like unit consisting of six edge-sharing triangles (Mn3), each of which is bridged by a μ3-oxygen atom.