The catalytic activities of 1-5 in reactions involving C-C and C-O bond formation have been studied, and the results indicated that complex 3 can be efficiently utilized as a heterogeneous bifunctional catalyst for the Knoevenagel condensation and multicomponent reactions to develop biologically important organic molecules. The luminescent properties of complexes were also studied. Interestingly, zinc complexes 1-3 showed strong lumniscent emission in the solid state, whereas cadmium complexes 4 and 5 exhibited bright luminescent emission in the solution phase. The semiconducting behavior of the complexes was studied by solid-state diffuse reflectance spectra (DRS), which showed optical band gaps in the range of 2.49-2.62 eV.Mixed-metal cyanides (Cu1/2Au1/2)CN, (Ag1/2Au1/2)CN, and (Cu1/3Ag1/3Au1/3)CN adopt an AuCN-type structure in which metal-cyanide chains pack on a hexagonal lattice with metal atoms arranged in sheets. The interactions between and within the metal-cyanide chains are investigated using density functional theory (DFT) calculations, 13C solid-state NMR (SSNMR), and X-ray pair distribution function (PDF) measurements. Long-range metal and cyanide order is found within the chains (-Cu-NC-Au-CN-)∞, (-Ag-NC-Au-CN-)∞, and (-Cu-NC-Ag-NC-Au-CN-)∞. Although Bragg diffraction studies establish that there is no long-range order between chains, X-ray PDF results show that there is local order between chains. In (Cu1/2Au1/2)CN and (Ag1/2Au1/2)CN, there is a preference for unlike metal atoms occurring as nearest neighbors within the metal sheets. A general mathematical proof shows that the maximum average number of heterometallic nearest-neighbor interactions on a hexagonal lattice with two types of metal atoms is four. Calculated energies of periodic structural models show that those with four unlike nearest neighbors are most favorable. Of these, models in space group Immm give the best fits to the X-ray PDF data out to 8 Å, providing good descriptions of the short- and medium-range structures. This result shows that interactions beyond those of nearest neighbors must be considered when determining the structures of these materials. Such interactions are also important in (Cu1/3Ag1/3Au1/3)CN, leading to the adoption of a structure in Pmm2 containing mixed Cu-Au and Ag-only sheets arranged to maximize the numbers of Cu···Au nearest- and next-nearest-neighbor interactions.The superfamily of heme copper oxidases reduces molecular oxygen or nitric oxide, and the active sites comprise a high-spin heme group (a3 or b3) and a non-heme metal (CuB or FeB). https://www.selleckchem.com/products/atuveciclib-bay-1143572.html The cbb3 C family of cytochrome c oxidases, with the high-spin heme b3 and CuB in the active site, is a subfamily of the heme copper oxidases that can reduce both molecular oxygen, which is the main substrate, and nitric oxide. The mechanism for NO reduction in cbb3 oxidase is studied here using hybrid density functional theory and compared to other cytochrome c oxidases (A and B families), with a high-spin heme a3 and CuB in the active site, and to cytochrome c dependent NO reductase, with a high-spin heme b3 and a non-heme FeB in the active site. It is found that the reaction mechanism and the detailed reaction energetics of the cbb3 oxidases are not similar to those of cytochrome c dependent NO reductase, which has the same type of high-spin heme group but a different non-heme metal. This is in contrast to earlier expectations. Instead, the NO reduction mechanism in cbb3 oxidases is very similar to that in the other cytochrome c oxidases, with the same non-heme metal, CuB, and is independent of the type of high-spin heme group. The conclusion is that the type of non-heme metal (CuB or FeB) in the active site of the heme copper oxidases is more important for the reaction mechanisms than the type of high-spin heme, at least for the NO reduction reaction. The reason is that the proton-coupled reduction potentials of the active site cofactors determine the energetics for the NO reduction reaction, and they depend to a larger extent on the non-heme metal. Observed differences in NO reduction reactivity among the various cytochrome c oxidases may be explained by differences outside the BNC, affecting the rate of proton transfer, rather than in the ****itself.An elaborate study with multireference second-order perturbation theory has been performed to elucidate the electronic structure and relative energy of three relevant states of FeNO corroles, namely the S = 0 ground state, the lowest S = 1 state, and the anion S = 1/2 state. On the basis of CASSCF and DMRG calculations with an active space including up to 37 orbitals, the electronic structure of the ground state was analyzed, with special emphasis on the diradical nature of the Fe-corrole and Fe-NO bonds. The results essentially confirm an earlier suggestion from B3LYP of a non-innocent corrole•2- bound to an FeNO7 unit, although the contribution of diradical character to the iron-corrole bond is found to be limited to 35%. This limited diradical character explains the high relative energy (16.5 kcal/mol) of the corresponding triplet state, where the corrole•2- is ferromagnetically coupled to the S = 1/2 FeNO7 unit. Consistent with experimental findings, reduction is found to take place at the corrole ligand, with a calculated electron affinity of 52.5 kcal/mol. The results obtained from the correlated calculations were also compared to DFT with a broad range of functionals.A series of new dimethyl-sulfoxide-containing pertechnetates and perrhenates of tetravalent U, Np, and Pu were synthesized and structurally characterized by the X-ray diffractometry. In all the synthesized compounds, the actinide atoms were coordinated by eight DMSO molecules with or without an extra XO4- anion in the coordination sphere. This resulted in the square antiprismatic or capped square antiprismatic coordination of An atoms. Three or four XO4- anions play the role of outer-sphere anions. The electron and IR spectra of the compounds correlated with their crystal structure.The composition-tuned, structure-modified, and morphology-controlled nanoscale metal-organic frameworks (MOFs) are quite important to improve the electrochemical performances for supercapacitors. In this work, a solvent-controlled method to prepare amino-functionalized bimetal MOFs with various morphologies is proposed. Three different morphologies of NiCo-MOFs, such as nanospheres, nanosheet-assembled hollow spheres (NSHSs), and rhombus sheets, have been successfully synthesized by using different solvents. The as-prepared three nanoscale NiCo-MOFs are comparatively characterized and are endowed a possible mechanism on nucleation and crystal growth controlling morphology. When used as electrode materials for supercapacitors, all NiCo-MOFs have excellent electrochemical properties. Specifically, the NiCo-MOF NSHS owns the best specific capacitance, which can achieve 1126.7 F g-1 at the current density of 0.5 A g-1 and maintain 93% of its original capacitance at the current density of 10 A g-1 after 3000 charge-discharge cycles.
The catalytic activities of 1-5 in reactions involving C-C and C-O bond formation have been studied, and the results indicated that complex 3 can be efficiently utilized as a heterogeneous bifunctional catalyst for the Knoevenagel condensation and multicomponent reactions to develop biologically important organic molecules. The luminescent properties of complexes were also studied. Interestingly, zinc complexes 1-3 showed strong lumniscent emission in the solid state, whereas cadmium complexes 4 and 5 exhibited bright luminescent emission in the solution phase. The semiconducting behavior of the complexes was studied by solid-state diffuse reflectance spectra (DRS), which showed optical band gaps in the range of 2.49-2.62 eV.Mixed-metal cyanides (Cu1/2Au1/2)CN, (Ag1/2Au1/2)CN, and (Cu1/3Ag1/3Au1/3)CN adopt an AuCN-type structure in which metal-cyanide chains pack on a hexagonal lattice with metal atoms arranged in sheets. The interactions between and within the metal-cyanide chains are investigated using density functional theory (DFT) calculations, 13C solid-state NMR (SSNMR), and X-ray pair distribution function (PDF) measurements. Long-range metal and cyanide order is found within the chains (-Cu-NC-Au-CN-)∞, (-Ag-NC-Au-CN-)∞, and (-Cu-NC-Ag-NC-Au-CN-)∞. Although Bragg diffraction studies establish that there is no long-range order between chains, X-ray PDF results show that there is local order between chains. In (Cu1/2Au1/2)CN and (Ag1/2Au1/2)CN, there is a preference for unlike metal atoms occurring as nearest neighbors within the metal sheets. A general mathematical proof shows that the maximum average number of heterometallic nearest-neighbor interactions on a hexagonal lattice with two types of metal atoms is four. Calculated energies of periodic structural models show that those with four unlike nearest neighbors are most favorable. Of these, models in space group Immm give the best fits to the X-ray PDF data out to 8 Å, providing good descriptions of the short- and medium-range structures. This result shows that interactions beyond those of nearest neighbors must be considered when determining the structures of these materials. Such interactions are also important in (Cu1/3Ag1/3Au1/3)CN, leading to the adoption of a structure in Pmm2 containing mixed Cu-Au and Ag-only sheets arranged to maximize the numbers of Cu···Au nearest- and next-nearest-neighbor interactions.The superfamily of heme copper oxidases reduces molecular oxygen or nitric oxide, and the active sites comprise a high-spin heme group (a3 or b3) and a non-heme metal (CuB or FeB). https://www.selleckchem.com/products/atuveciclib-bay-1143572.html The cbb3 C family of cytochrome c oxidases, with the high-spin heme b3 and CuB in the active site, is a subfamily of the heme copper oxidases that can reduce both molecular oxygen, which is the main substrate, and nitric oxide. The mechanism for NO reduction in cbb3 oxidase is studied here using hybrid density functional theory and compared to other cytochrome c oxidases (A and B families), with a high-spin heme a3 and CuB in the active site, and to cytochrome c dependent NO reductase, with a high-spin heme b3 and a non-heme FeB in the active site. It is found that the reaction mechanism and the detailed reaction energetics of the cbb3 oxidases are not similar to those of cytochrome c dependent NO reductase, which has the same type of high-spin heme group but a different non-heme metal. This is in contrast to earlier expectations. Instead, the NO reduction mechanism in cbb3 oxidases is very similar to that in the other cytochrome c oxidases, with the same non-heme metal, CuB, and is independent of the type of high-spin heme group. The conclusion is that the type of non-heme metal (CuB or FeB) in the active site of the heme copper oxidases is more important for the reaction mechanisms than the type of high-spin heme, at least for the NO reduction reaction. The reason is that the proton-coupled reduction potentials of the active site cofactors determine the energetics for the NO reduction reaction, and they depend to a larger extent on the non-heme metal. Observed differences in NO reduction reactivity among the various cytochrome c oxidases may be explained by differences outside the BNC, affecting the rate of proton transfer, rather than in the BNC itself.An elaborate study with multireference second-order perturbation theory has been performed to elucidate the electronic structure and relative energy of three relevant states of FeNO corroles, namely the S = 0 ground state, the lowest S = 1 state, and the anion S = 1/2 state. On the basis of CASSCF and DMRG calculations with an active space including up to 37 orbitals, the electronic structure of the ground state was analyzed, with special emphasis on the diradical nature of the Fe-corrole and Fe-NO bonds. The results essentially confirm an earlier suggestion from B3LYP of a non-innocent corrole•2- bound to an FeNO7 unit, although the contribution of diradical character to the iron-corrole bond is found to be limited to 35%. This limited diradical character explains the high relative energy (16.5 kcal/mol) of the corresponding triplet state, where the corrole•2- is ferromagnetically coupled to the S = 1/2 FeNO7 unit. Consistent with experimental findings, reduction is found to take place at the corrole ligand, with a calculated electron affinity of 52.5 kcal/mol. The results obtained from the correlated calculations were also compared to DFT with a broad range of functionals.A series of new dimethyl-sulfoxide-containing pertechnetates and perrhenates of tetravalent U, Np, and Pu were synthesized and structurally characterized by the X-ray diffractometry. In all the synthesized compounds, the actinide atoms were coordinated by eight DMSO molecules with or without an extra XO4- anion in the coordination sphere. This resulted in the square antiprismatic or capped square antiprismatic coordination of An atoms. Three or four XO4- anions play the role of outer-sphere anions. The electron and IR spectra of the compounds correlated with their crystal structure.The composition-tuned, structure-modified, and morphology-controlled nanoscale metal-organic frameworks (MOFs) are quite important to improve the electrochemical performances for supercapacitors. In this work, a solvent-controlled method to prepare amino-functionalized bimetal MOFs with various morphologies is proposed. Three different morphologies of NiCo-MOFs, such as nanospheres, nanosheet-assembled hollow spheres (NSHSs), and rhombus sheets, have been successfully synthesized by using different solvents. The as-prepared three nanoscale NiCo-MOFs are comparatively characterized and are endowed a possible mechanism on nucleation and crystal growth controlling morphology. When used as electrode materials for supercapacitors, all NiCo-MOFs have excellent electrochemical properties. Specifically, the NiCo-MOF NSHS owns the best specific capacitance, which can achieve 1126.7 F g-1 at the current density of 0.5 A g-1 and maintain 93% of its original capacitance at the current density of 10 A g-1 after 3000 charge-discharge cycles.
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