A new binuclear Cu(Ⅱ) complex with nitronyl nitroxide radicals [Cu(NIT3Py)2Cl2]2(NIT3Py = 2-(3'-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been synthesized and structurally characterized b...A new binuclear Cu(Ⅱ) complex with nitronyl nitroxide radicals [Cu(NIT3Py)2Cl2]2(NIT3Py = 2-(3'-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been synthesized and structurally characterized by X-ray diffraction analysis.It crystallizes in monoclinic,space group C2/c with a = 38.483(4),b = 7.2450(8),c = 27.559(3) ,β = 134.0180(10)°,V = 5525.6(10) 3,C48H64Cl4Cu2N12O8,Mr = 1206.00,Z = 4,Dc = 1.450 g/cm3,μ(MoKα) = 1.025 mm-1,F(000) = 2504,S = 1.066,the final R = 0.0471 and wR = 0.1121 for 3286 observed reflections(I 2σ(I)).The title complex consists of centrosymmetric dinuclear units [Cu(NIT3Py)2Cl2]2,in which the copper ions are square-pyramidally coordinated by two pyridyl nitrogen atoms of two radical ligands and three chlorine anions,two of which bridge the copper ions.The magnetic measurements show ferromagnetic interactions between the copper ions and the radical ligands.展开更多
Elucidation of the CuOx-CeO2 interactions is of great interest and importance in understanding complex CuOx-CeO2 interfacial catalysis in various reactions. In the present work, we have investigated structures and cat...Elucidation of the CuOx-CeO2 interactions is of great interest and importance in understanding complex CuOx-CeO2 interfacial catalysis in various reactions. In the present work, we have investigated structures and catalytic activity in CO oxidation of CuOx species on CeO2 rods, cubes and polyhedra predominantly exposing {110}+{100}, {100} and {111} facets by the incipient wetness impregnation method with the lowest Cu loading of 0.025%. The structural evolution of CuOx species was found to depend on both the Cu loading and the CeO2 morphology. As the Cu loading increases, CuOx species are deposited preferentially on the surface defect of CeO2 and then aggregate and grow, accompanied by the formation of isolated Cu ions, CuOx clusters strongly/weakly interacting with the CeO2, highly dispersed Cu O nanoparticles, and large Cu O nanoparticles. The isolated Cu^+ species and CuOx clusters weakly interacting with the CeO2 were observed mainly on the O-terminated CeO2{100} facets. Meanwhile, more Cu(I) species are stabilized during CO reduction processes in CuOx/c-CeO2 catalysts than in CuOx/r-CeO2 and CuOx/p-CeO2 catalysts. The catalytic activities of various CuOx/CeO2 catalysts in CO oxidation vary with both the CuOx species and the CeO2 morphology. These results comprehensively elucidate the CuOx-CeO2 interactions and exemplify their morphology-dependence.展开更多
Interaction rule between representative RE and Sn, Sb, Pb, Cu, S, P low melting point elements respectively in Fe , Cu , Al , Ni base liquid solutions including totally 34 ternary and quarternary systems was inve...Interaction rule between representative RE and Sn, Sb, Pb, Cu, S, P low melting point elements respectively in Fe , Cu , Al , Ni base liquid solutions including totally 34 ternary and quarternary systems was investigated. For each system some thermodynamic properties were obtained, such as the standard free energies of equilibrium reactions, activity interaction coefficients etc ..展开更多
o understand the driving forces leading to mixed-ligand complexes in biologi-cal systenis.ternary complexes of M (ATP(L ̄(2-) type, where M = Cu ̄(2+), Ni ̄(2+) orCo ̄(2+) , and L= pyridine(Py) , 4-picoline, 3, 5-lut...o understand the driving forces leading to mixed-ligand complexes in biologi-cal systenis.ternary complexes of M (ATP(L ̄(2-) type, where M = Cu ̄(2+), Ni ̄(2+) orCo ̄(2+) , and L= pyridine(Py) , 4-picoline, 3, 5-lutidine, isoquinoline (lq) or benzimi-dazole(Bi) in aqueous solution were studied by spectropliotometry, some of them(M=Cu ̄(2+), L = isoquinoline or benzimidazole) were also separately studied hy po-tentiometric pH titration. The results show that an intramolecular stacking interac-tion exists between the heteroaromatic ring of the ligands and the purine moiety ofATP.展开更多
The equilibrium product in Fe-Cu-Ce,Fe-P-Ce or Fe-Ti-Ce solution have ben Mentified to be Ce_2O_2S,but not the intermetallic compounds of Ce against Cu,P or Ti.The equilibrium eonstant of Ce_2O_2S=2[Ce]+2[O]+[S] and t...The equilibrium product in Fe-Cu-Ce,Fe-P-Ce or Fe-Ti-Ce solution have ben Mentified to be Ce_2O_2S,but not the intermetallic compounds of Ce against Cu,P or Ti.The equilibrium eonstant of Ce_2O_2S=2[Ce]+2[O]+[S] and the interaction coefficients between solutes in Fe-base solution have been determined as follows: K_(Ce_2O_2S)=2.57×10^(-5) e_(Ce)^(Cu)=-0.49;e_(Ce)~P=1.77;e_(Ce)^(Ti)=-3.62 e_(Cu)^(Ce)=-0.22;e_P^(Ce)=0.39;e_(Ti)^(Ce)=-1.23 ε_(Ce)^(Cu)=-128.0;ε_(Ce)~P=-224.1;ε_(Ce)^(Ti)=-710.0 Ce decreases the activities of Cu and Ti in Fe-base solution and increases their solubifities,as well as increases the activity of P and decreases its solubility.展开更多
The interactions of the complexes of Cu(phen) 2+ 2 and Cu(bpy) 2+ 2 with DNA were investigated with electrochemistry and spectroelectrochemistry. Binding constants( K n + ) and the reaction model wer...The interactions of the complexes of Cu(phen) 2+ 2 and Cu(bpy) 2+ 2 with DNA were investigated with electrochemistry and spectroelectrochemistry. Binding constants( K n + ) and the reaction model were obtained from their electrochemical behavior and electrochemical data. The binding constants( K 2+ ) for Cu(phen) 2+ 2 DNA and Cu(bpy) 2+ 2 DNA were 8 51×10 3 L·mol -1 and 3 27×10 3 L·mol -1 , and K +s were 3 09×10 4 L·mol -1 and 5 66×10 3 L·mol -1 respectively. The spectroscopic characteristics of the complexes of Cu(phen) 2+ 2 DNA and Cu(bpy) 2+ 2 DNA were studied in detail. Some significant spectroelectrochemical data were obtained. The interaction of DNA with complexes was described.展开更多
Activitibs of Si in binary Cu-Si and ternary Cu-Ti-Si melts were measured at 1 550℃ by using a method of chemical equilIbrium between gas and liquid. The activity interaction coefficients of Si in the melts have been...Activitibs of Si in binary Cu-Si and ternary Cu-Ti-Si melts were measured at 1 550℃ by using a method of chemical equilIbrium between gas and liquid. The activity interaction coefficients of Si in the melts have been determined from the experimental data (lny = -5.69. s = 6.69. P2: = -26.22. E; =-43.96) and activity interaction coefficients of Ti in binary Cu-Ti melt at 1550℃ has been estimated from Sommer's data based on the regular solution model (lny =-1 .10. : = 2.95.p:=-2.10).展开更多
In the previous paper,the geometry of the triatomic clusters for Cu, Ag,and An was obtained using the Dy-Xa method. In this investigation the atomic. orbital interactions of atom Cu, Ag, An in the triatomic clusters a...In the previous paper,the geometry of the triatomic clusters for Cu, Ag,and An was obtained using the Dy-Xa method. In this investigation the atomic. orbital interactions of atom Cu, Ag, An in the triatomic clusters are analyzed. The magnitudes of the atomic orbital interactions of the atoms in the clusters are measured by the splitting of corresponding atomic orbital. The calculation results show the atomic orbital interactions of Cu triatomic cluster differ greatly from those of Ag and Au triatomic cluster house of the mixture radio of 4s-Orbital with 3d-Orbital in the Cu cluster more than those in the Ag and Au cluster. The values of atomic orbital interactions of Au in the of cluster are larger than corresponding atomic Orbital interactions of Ag in the cluster.展开更多
In this paper, the total energies and the density of the states of triatomic systems of Cu. Ag. and An were calculated by discret-variational Xa method. Furthermore, the optimized geometry of triatomic copper,silver, ...In this paper, the total energies and the density of the states of triatomic systems of Cu. Ag. and An were calculated by discret-variational Xa method. Furthermore, the optimized geometry of triatomic copper,silver, and gold clusters were obtained. The results showed that the optimaaed geometry of Cu3 was different from that of Ag3. and An3. Cu3 cluster has two nearlydegenerate candidates for the ground state. Ag3 and Au3 clusters have bent isosceles triangular structure only. The ground configuration for the triatomic clusters is and the ground state is 2B2. The present evidences arc in agreement results with the experimental and with those by other complex theoretical method.展开更多
To study the Cu-Cu interaction and stability of the title complexes,the structures of complexes [Cu(Ph2Ppy)(CH3CN)]+ 1,[Cu(Ph2Ppy)]+ 2,[Cu2(Ph2Ppy)2(CH3CN)2]2+ 3,[Cu2(Ph2Ppy)2(CH3CN)]2+ 4,[Cu2(Ph2Pp...To study the Cu-Cu interaction and stability of the title complexes,the structures of complexes [Cu(Ph2Ppy)(CH3CN)]+ 1,[Cu(Ph2Ppy)]+ 2,[Cu2(Ph2Ppy)2(CH3CN)2]2+ 3,[Cu2(Ph2Ppy)2(CH3CN)]2+ 4,[Cu2(Ph2Ppy)2]2+ 5 and [Cu2(Ph2Ppy)3(CH3CN)]2+ 6 were calculated by density functional theory PBE0 method,and the following conclusions can be drawn:(1) There is no orbital overlapping between two Cu atoms,indicating no Cu-Cu orbital interaction exists in complexes 3~6.Due to a breakdown of the closed shell configuration of Cu atoms,the weak Cu-Cu interactions result from the 3dCu → 4sCu' charge-transfer in 4~6.The Cu-Cu interaction strength follows 5 〉 6 〉 4,implying that there are stronger Cu-Cu interactions in the complexes with fewer CH3CN or more Ph2Ppy ligands.(2) The calculated interaction energies suggest that the coordination of Cu to Ph2Ppy is stronger than that to CH3CN.In 3~6,there are weaker interactions between Cu and CH3CN or Ph2Ppy in the complexes with more CH3CN or Ph2Ppy ligands.(3) The P-Cu and N-Cu interactions are much stronger than the Cu-Cu interaction,so we mainly attribute the stabilities of the binuclear complexes to the eight-membered rings Cu2P2N2C2.展开更多
Photocatalytic H2 evolution reactions on pristine graphitic carbon nitrides(g-C3N4),as a promising approach for converting solar energy to fuel,are attractive for tackling global energy concerns but still suffer from ...Photocatalytic H2 evolution reactions on pristine graphitic carbon nitrides(g-C3N4),as a promising approach for converting solar energy to fuel,are attractive for tackling global energy concerns but still suffer from low efficiencies.In this article,we report a tractable approach to modifying g-C3N4 with vanadyl phthalocyanine(VOPc/CN)for efficient visible-light-driven hydrogen production.A non-covalent VOPc/CN hybrid photocatalyst formed viaπ-πstacking interactions between the two components,as confirmed by analysis of UV-vis absorption spectra.The VOPc/CN hybrid photocatalyst shows excellent visible-light-driven photocatalytic performance and good stability.Under optimal conditions,the corresponding H2 evolution rate is nearly 6 times higher than that of pure g-C3N4.The role of VOPc in promoting hydrogen evolution activity was to extend the visible light absorption range and prevent the recombination of photoexcited electron-hole pairs effectively.It is expected that this facile modification method could be a new inspiration for the rational design and exploration of g-C3N4-based hybrid systems with strong light absorption and high-efficiency carrier separation.展开更多
Solvothermal reactions of 4,4'-oxybis(benzoic acid) (H2oba) with 1,3-dipyridyl benzene (1,3-dpb) produced a two-dimensional (2D) cadmium(Ⅱ) coordination polymer {[Cd(oba)(dpb)]·H2O}n (1). The co...Solvothermal reactions of 4,4'-oxybis(benzoic acid) (H2oba) with 1,3-dipyridyl benzene (1,3-dpb) produced a two-dimensional (2D) cadmium(Ⅱ) coordination polymer {[Cd(oba)(dpb)]·H2O}n (1). The complex was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/c with a = 13.6692(9), b = 25.9647(17), c = 8.7912(6) , α = 125.0370(10), γ = 2544.7(3)°, V = 2544.7(3) 3, C30H22N2O6Cd, Mr = 618.91, Dc =1.609 g/cm3, F(000) = 1248, μ = 0.904 mm-1 and Z = 4. The neighboring Cd(Ⅱ) ions are linked by oba2-anions and 1,3-dpb to form an infinitely 2D wavelike sheet, and two such 2D sheets are interlocked with each other by H-bonding to form a 2D → 2D structure. The adjacent two groups of interlocked structures are further linked to form a bilayer 2D supramolecular network by π-π interactions. In addition, the fluorescence property of 1 was also studied.展开更多
Driven by safety issues,environmental concerns,and high costs,rechargeable aqueous zinc-ion batteries(ZIBs)have received increasing attention in recent years owing to their unique advantages.However,the sluggish kinet...Driven by safety issues,environmental concerns,and high costs,rechargeable aqueous zinc-ion batteries(ZIBs)have received increasing attention in recent years owing to their unique advantages.However,the sluggish kinetics of divalent charge Zn^(2+)in the cathode materials caused by the strong electrostatic interaction and their unsatisfactory cycle life hinder the development of ZIBs.Herein,organic cations and Zn^(2+)ions co-pre-inserted vanadium oxide([N(CH_(3))_(4)]_(0.77),Zn_(0.23))V_(8)O_(20)·3.8H_(2)O are reported as the cathode for ultra-stable aqueous ZIBs,in which the weaker electrostatic interactions between Zn^(2+)and organic ion-pinned vanadium oxide can induce the high reversibility of Zn^(2+)insertion and extraction,thereby improving the cycle life.It is demonstrated that([N(CH_(3))_(4)]_(0.77),Zn_(0.23))V_(8)O_(20)·3.8H_(2)O cathodes deliver a discharge capacity of 181 mA h g^(-1)at8 A g^(-1)and ultra-long life span(99.5%capacity retention after 2000 cycles).A reversible Zn^(2+)/H^(+)ions(de)intercalation storage process and pseudocapacitive charge storage are characterized.The weaker interactions between organic ion and Zn^(2+)open a novel avenue for the design of highly reversible cathode materials with long-term cycling stability.展开更多
Two series of lanthanide compounds, namely, chlorides containing different numbers of both 1,10-phenanthroline (Phen) molecules and chloride anions in the first coordination sphere, and Schiff Bases (SBs) derived ...Two series of lanthanide compounds, namely, chlorides containing different numbers of both 1,10-phenanthroline (Phen) molecules and chloride anions in the first coordination sphere, and Schiff Bases (SBs) derived from Pyridoxal (PL) and amino acids, were characterized by single crystal X-ray diffraction and luminescence techniques. The combined use of these techniques for the analysis of long-distance europium non-covalent interactions was performed for the first time. As a result, the correlation between supramolecular organization and the features of the Eum electronic transitions was found for the compounds of the first series. Strong non-covalent interactions between pyridoxal tings of SBs (the second series of compotmd) led to the formation of 1:2 species and four-dentate coordination function of these SBs in aqueous solution.展开更多
In this paper, by using harmonic-oscillator wave functions of different interaction models, i.e. OPE (onepion-exchange model), OPsE (only pseudoscalar meson exchange model), the extended GBE (Goldstone-boson-exchange ...In this paper, by using harmonic-oscillator wave functions of different interaction models, i.e. OPE (onepion-exchange model), OPsE (only pseudoscalar meson exchange model), the extended GBE (Goldstone-boson-exchange model including vector and scalar mesons), and OGE (one-gluon-exchange model), we calculate and compare the strong decays of negative parity N* resonances under 2 GeV. We find that the conventional mixing angles are correct, and GBE and OGE are obviously superior to OPE and OPsE.展开更多
Five optimized geometries of F-?(H2O)n (n = 1, 2) were obtained with ab initio calculation at the B3LYP/6-311++G** level. The accurate intermonomer interaction energy was calculated using the MP2 electron correlation ...Five optimized geometries of F-?(H2O)n (n = 1, 2) were obtained with ab initio calculation at the B3LYP/6-311++G** level. The accurate intermonomer interaction energy was calculated using the MP2 electron correlation correction as well as the basis set superposition error correction by the Boys-Bernardi “counterpoise” protocol. Natural bond orbital (NBO) theory was applied to quantify the relative strength of these interactions and account for their effects on the stability, structural and vibrational parameters of Fˉ?(H2O)n (n = 1, 2). It is shown that the charge transferring from the lone pair of F-1 to the σ?OH(…F) antibonding orbital is important. The results indicate the occupancy of σ?OH(…F) is increased (denoted ?σ?OH(…F)) and the σOH(…F) bond is leng- thened (denoted ?ROH(…F)), leading to the red-shift and the red-shift values have linear correlation with both ?σ?OH(…F) and ?ROH(…F).展开更多
基金supported by the National Natural Science Foundation of China (No. 20901059)the Technological Development Foundation Project of Tianjin Educational Committee (No. 20080503)
文摘A new binuclear Cu(Ⅱ) complex with nitronyl nitroxide radicals [Cu(NIT3Py)2Cl2]2(NIT3Py = 2-(3'-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been synthesized and structurally characterized by X-ray diffraction analysis.It crystallizes in monoclinic,space group C2/c with a = 38.483(4),b = 7.2450(8),c = 27.559(3) ,β = 134.0180(10)°,V = 5525.6(10) 3,C48H64Cl4Cu2N12O8,Mr = 1206.00,Z = 4,Dc = 1.450 g/cm3,μ(MoKα) = 1.025 mm-1,F(000) = 2504,S = 1.066,the final R = 0.0471 and wR = 0.1121 for 3286 observed reflections(I 2σ(I)).The title complex consists of centrosymmetric dinuclear units [Cu(NIT3Py)2Cl2]2,in which the copper ions are square-pyramidally coordinated by two pyridyl nitrogen atoms of two radical ligands and three chlorine anions,two of which bridge the copper ions.The magnetic measurements show ferromagnetic interactions between the copper ions and the radical ligands.
文摘Elucidation of the CuOx-CeO2 interactions is of great interest and importance in understanding complex CuOx-CeO2 interfacial catalysis in various reactions. In the present work, we have investigated structures and catalytic activity in CO oxidation of CuOx species on CeO2 rods, cubes and polyhedra predominantly exposing {110}+{100}, {100} and {111} facets by the incipient wetness impregnation method with the lowest Cu loading of 0.025%. The structural evolution of CuOx species was found to depend on both the Cu loading and the CeO2 morphology. As the Cu loading increases, CuOx species are deposited preferentially on the surface defect of CeO2 and then aggregate and grow, accompanied by the formation of isolated Cu ions, CuOx clusters strongly/weakly interacting with the CeO2, highly dispersed Cu O nanoparticles, and large Cu O nanoparticles. The isolated Cu^+ species and CuOx clusters weakly interacting with the CeO2 were observed mainly on the O-terminated CeO2{100} facets. Meanwhile, more Cu(I) species are stabilized during CO reduction processes in CuOx/c-CeO2 catalysts than in CuOx/r-CeO2 and CuOx/p-CeO2 catalysts. The catalytic activities of various CuOx/CeO2 catalysts in CO oxidation vary with both the CuOx species and the CeO2 morphology. These results comprehensively elucidate the CuOx-CeO2 interactions and exemplify their morphology-dependence.
基金Project Sponsored by the National Natural Science Foundation
文摘Interaction rule between representative RE and Sn, Sb, Pb, Cu, S, P low melting point elements respectively in Fe , Cu , Al , Ni base liquid solutions including totally 34 ternary and quarternary systems was investigated. For each system some thermodynamic properties were obtained, such as the standard free energies of equilibrium reactions, activity interaction coefficients etc ..
文摘o understand the driving forces leading to mixed-ligand complexes in biologi-cal systenis.ternary complexes of M (ATP(L ̄(2-) type, where M = Cu ̄(2+), Ni ̄(2+) orCo ̄(2+) , and L= pyridine(Py) , 4-picoline, 3, 5-lutidine, isoquinoline (lq) or benzimi-dazole(Bi) in aqueous solution were studied by spectropliotometry, some of them(M=Cu ̄(2+), L = isoquinoline or benzimidazole) were also separately studied hy po-tentiometric pH titration. The results show that an intramolecular stacking interac-tion exists between the heteroaromatic ring of the ligands and the purine moiety ofATP.
文摘The equilibrium product in Fe-Cu-Ce,Fe-P-Ce or Fe-Ti-Ce solution have ben Mentified to be Ce_2O_2S,but not the intermetallic compounds of Ce against Cu,P or Ti.The equilibrium eonstant of Ce_2O_2S=2[Ce]+2[O]+[S] and the interaction coefficients between solutes in Fe-base solution have been determined as follows: K_(Ce_2O_2S)=2.57×10^(-5) e_(Ce)^(Cu)=-0.49;e_(Ce)~P=1.77;e_(Ce)^(Ti)=-3.62 e_(Cu)^(Ce)=-0.22;e_P^(Ce)=0.39;e_(Ti)^(Ce)=-1.23 ε_(Ce)^(Cu)=-128.0;ε_(Ce)~P=-224.1;ε_(Ce)^(Ti)=-710.0 Ce decreases the activities of Cu and Ti in Fe-base solution and increases their solubifities,as well as increases the activity of P and decreases its solubility.
文摘The interactions of the complexes of Cu(phen) 2+ 2 and Cu(bpy) 2+ 2 with DNA were investigated with electrochemistry and spectroelectrochemistry. Binding constants( K n + ) and the reaction model were obtained from their electrochemical behavior and electrochemical data. The binding constants( K 2+ ) for Cu(phen) 2+ 2 DNA and Cu(bpy) 2+ 2 DNA were 8 51×10 3 L·mol -1 and 3 27×10 3 L·mol -1 , and K +s were 3 09×10 4 L·mol -1 and 5 66×10 3 L·mol -1 respectively. The spectroscopic characteristics of the complexes of Cu(phen) 2+ 2 DNA and Cu(bpy) 2+ 2 DNA were studied in detail. Some significant spectroelectrochemical data were obtained. The interaction of DNA with complexes was described.
文摘Activitibs of Si in binary Cu-Si and ternary Cu-Ti-Si melts were measured at 1 550℃ by using a method of chemical equilIbrium between gas and liquid. The activity interaction coefficients of Si in the melts have been determined from the experimental data (lny = -5.69. s = 6.69. P2: = -26.22. E; =-43.96) and activity interaction coefficients of Ti in binary Cu-Ti melt at 1550℃ has been estimated from Sommer's data based on the regular solution model (lny =-1 .10. : = 2.95.p:=-2.10).
文摘In the previous paper,the geometry of the triatomic clusters for Cu, Ag,and An was obtained using the Dy-Xa method. In this investigation the atomic. orbital interactions of atom Cu, Ag, An in the triatomic clusters are analyzed. The magnitudes of the atomic orbital interactions of the atoms in the clusters are measured by the splitting of corresponding atomic orbital. The calculation results show the atomic orbital interactions of Cu triatomic cluster differ greatly from those of Ag and Au triatomic cluster house of the mixture radio of 4s-Orbital with 3d-Orbital in the Cu cluster more than those in the Ag and Au cluster. The values of atomic orbital interactions of Au in the of cluster are larger than corresponding atomic Orbital interactions of Ag in the cluster.
文摘In this paper, the total energies and the density of the states of triatomic systems of Cu. Ag. and An were calculated by discret-variational Xa method. Furthermore, the optimized geometry of triatomic copper,silver, and gold clusters were obtained. The results showed that the optimaaed geometry of Cu3 was different from that of Ag3. and An3. Cu3 cluster has two nearlydegenerate candidates for the ground state. Ag3 and Au3 clusters have bent isosceles triangular structure only. The ground configuration for the triatomic clusters is and the ground state is 2B2. The present evidences arc in agreement results with the experimental and with those by other complex theoretical method.
基金Supported by the Natural Science Foundation of Guangdong Province (No. 5005938)Research Project of Ministry of Education and Guangdong Province,China (2007A090302046)
文摘To study the Cu-Cu interaction and stability of the title complexes,the structures of complexes [Cu(Ph2Ppy)(CH3CN)]+ 1,[Cu(Ph2Ppy)]+ 2,[Cu2(Ph2Ppy)2(CH3CN)2]2+ 3,[Cu2(Ph2Ppy)2(CH3CN)]2+ 4,[Cu2(Ph2Ppy)2]2+ 5 and [Cu2(Ph2Ppy)3(CH3CN)]2+ 6 were calculated by density functional theory PBE0 method,and the following conclusions can be drawn:(1) There is no orbital overlapping between two Cu atoms,indicating no Cu-Cu orbital interaction exists in complexes 3~6.Due to a breakdown of the closed shell configuration of Cu atoms,the weak Cu-Cu interactions result from the 3dCu → 4sCu' charge-transfer in 4~6.The Cu-Cu interaction strength follows 5 〉 6 〉 4,implying that there are stronger Cu-Cu interactions in the complexes with fewer CH3CN or more Ph2Ppy ligands.(2) The calculated interaction energies suggest that the coordination of Cu to Ph2Ppy is stronger than that to CH3CN.In 3~6,there are weaker interactions between Cu and CH3CN or Ph2Ppy in the complexes with more CH3CN or Ph2Ppy ligands.(3) The P-Cu and N-Cu interactions are much stronger than the Cu-Cu interaction,so we mainly attribute the stabilities of the binuclear complexes to the eight-membered rings Cu2P2N2C2.
基金supported by the National Natural Science Foundation of China(51572253,21771171)Scientific Research Grant of Hefei National Synchrotron Radiation Laboratory(UN2017LHJJ)+1 种基金the Fundamental Research Funds for the Central Universitiescooperation between NSFC and Netherlands Organization for Scientific Research(51561135011)~~
文摘Photocatalytic H2 evolution reactions on pristine graphitic carbon nitrides(g-C3N4),as a promising approach for converting solar energy to fuel,are attractive for tackling global energy concerns but still suffer from low efficiencies.In this article,we report a tractable approach to modifying g-C3N4 with vanadyl phthalocyanine(VOPc/CN)for efficient visible-light-driven hydrogen production.A non-covalent VOPc/CN hybrid photocatalyst formed viaπ-πstacking interactions between the two components,as confirmed by analysis of UV-vis absorption spectra.The VOPc/CN hybrid photocatalyst shows excellent visible-light-driven photocatalytic performance and good stability.Under optimal conditions,the corresponding H2 evolution rate is nearly 6 times higher than that of pure g-C3N4.The role of VOPc in promoting hydrogen evolution activity was to extend the visible light absorption range and prevent the recombination of photoexcited electron-hole pairs effectively.It is expected that this facile modification method could be a new inspiration for the rational design and exploration of g-C3N4-based hybrid systems with strong light absorption and high-efficiency carrier separation.
基金supported by the National Natural Science Foundation of China (21071004, 51173002)the Start-up Foundation and the young teacher’s research foundation of Anhui University of Science and Technology (11227, 2012QNZ08)the Research fund of Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province (AE 201107)
文摘Solvothermal reactions of 4,4'-oxybis(benzoic acid) (H2oba) with 1,3-dipyridyl benzene (1,3-dpb) produced a two-dimensional (2D) cadmium(Ⅱ) coordination polymer {[Cd(oba)(dpb)]·H2O}n (1). The complex was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/c with a = 13.6692(9), b = 25.9647(17), c = 8.7912(6) , α = 125.0370(10), γ = 2544.7(3)°, V = 2544.7(3) 3, C30H22N2O6Cd, Mr = 618.91, Dc =1.609 g/cm3, F(000) = 1248, μ = 0.904 mm-1 and Z = 4. The neighboring Cd(Ⅱ) ions are linked by oba2-anions and 1,3-dpb to form an infinitely 2D wavelike sheet, and two such 2D sheets are interlocked with each other by H-bonding to form a 2D → 2D structure. The adjacent two groups of interlocked structures are further linked to form a bilayer 2D supramolecular network by π-π interactions. In addition, the fluorescence property of 1 was also studied.
基金supported by the funding from the National Natural Science Foundation of China(grant nos.51902187,52072224,and 51732007)the Natural Science Foundation of Shandong Province(ZR2018BEM010)+3 种基金the Science Fund for Distinguished Young Scholars of Shandong Province(ZR2019JQ16)the Fundamental Research Funds of Shandong UniversityYoung Elite Scientist Sponsorship Program by CAST(YESS)the support from Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong
文摘Driven by safety issues,environmental concerns,and high costs,rechargeable aqueous zinc-ion batteries(ZIBs)have received increasing attention in recent years owing to their unique advantages.However,the sluggish kinetics of divalent charge Zn^(2+)in the cathode materials caused by the strong electrostatic interaction and their unsatisfactory cycle life hinder the development of ZIBs.Herein,organic cations and Zn^(2+)ions co-pre-inserted vanadium oxide([N(CH_(3))_(4)]_(0.77),Zn_(0.23))V_(8)O_(20)·3.8H_(2)O are reported as the cathode for ultra-stable aqueous ZIBs,in which the weaker electrostatic interactions between Zn^(2+)and organic ion-pinned vanadium oxide can induce the high reversibility of Zn^(2+)insertion and extraction,thereby improving the cycle life.It is demonstrated that([N(CH_(3))_(4)]_(0.77),Zn_(0.23))V_(8)O_(20)·3.8H_(2)O cathodes deliver a discharge capacity of 181 mA h g^(-1)at8 A g^(-1)and ultra-long life span(99.5%capacity retention after 2000 cycles).A reversible Zn^(2+)/H^(+)ions(de)intercalation storage process and pseudocapacitive charge storage are characterized.The weaker interactions between organic ion and Zn^(2+)open a novel avenue for the design of highly reversible cathode materials with long-term cycling stability.
基金Russian Science Support Foundation, Russian Foundation of Basic Research (07-03-12196 and grant MK-6026.2008.9)
文摘Two series of lanthanide compounds, namely, chlorides containing different numbers of both 1,10-phenanthroline (Phen) molecules and chloride anions in the first coordination sphere, and Schiff Bases (SBs) derived from Pyridoxal (PL) and amino acids, were characterized by single crystal X-ray diffraction and luminescence techniques. The combined use of these techniques for the analysis of long-distance europium non-covalent interactions was performed for the first time. As a result, the correlation between supramolecular organization and the features of the Eum electronic transitions was found for the compounds of the first series. Strong non-covalent interactions between pyridoxal tings of SBs (the second series of compotmd) led to the formation of 1:2 species and four-dentate coordination function of these SBs in aqueous solution.
文摘In this paper, by using harmonic-oscillator wave functions of different interaction models, i.e. OPE (onepion-exchange model), OPsE (only pseudoscalar meson exchange model), the extended GBE (Goldstone-boson-exchange model including vector and scalar mesons), and OGE (one-gluon-exchange model), we calculate and compare the strong decays of negative parity N* resonances under 2 GeV. We find that the conventional mixing angles are correct, and GBE and OGE are obviously superior to OPE and OPsE.
基金This work was supported by the Foundation of Education Committee of Gansu Province (021-227).
文摘Five optimized geometries of F-?(H2O)n (n = 1, 2) were obtained with ab initio calculation at the B3LYP/6-311++G** level. The accurate intermonomer interaction energy was calculated using the MP2 electron correlation correction as well as the basis set superposition error correction by the Boys-Bernardi “counterpoise” protocol. Natural bond orbital (NBO) theory was applied to quantify the relative strength of these interactions and account for their effects on the stability, structural and vibrational parameters of Fˉ?(H2O)n (n = 1, 2). It is shown that the charge transferring from the lone pair of F-1 to the σ?OH(…F) antibonding orbital is important. The results indicate the occupancy of σ?OH(…F) is increased (denoted ?σ?OH(…F)) and the σOH(…F) bond is leng- thened (denoted ?ROH(…F)), leading to the red-shift and the red-shift values have linear correlation with both ?σ?OH(…F) and ?ROH(…F).