As a promising anode material for magnesium ion rechargeable batteries,magnesium metavanadate(MgV_(2)O_(6))has attracted considerable research interest in recent years.A MgV_(2)O_(6)sample was synthesized via a facile...As a promising anode material for magnesium ion rechargeable batteries,magnesium metavanadate(MgV_(2)O_(6))has attracted considerable research interest in recent years.A MgV_(2)O_(6)sample was synthesized via a facile solid-state reaction by multistep-firing stoichiometric mixtures of MgO and V2O5 powder under an air atmosphere.The solid-state phase transition fromα-MgV_(2)O_(6)toβ-MgV_(2)O_(6)occurred at 841 K and the enthalpy change was 4.37±0.04 kJ/mol.The endothermic effect at 1014 K and the enthalpy change was 26.54±0.26 kJ/mol,which is related to the incongruent melting ofβ-MgV_(2)O_(6).In situ XRD was performed to investigate phase transition of the as-prepared MgV_(2)O_(6)at high temperatures.The cell parameters obtained by Rietveld refinement indicated that it crystallizes in a monoclinic system with the C2/m space group,and the lattice parameters of a=9.280 A°,b=3.501 A°,c=6.731 A°,β=111.76°.The solid-state phase transition fromα-MgV_(2)O_(6)toβ-MgV_(2)O_(6)was further studied by thermal kinetics,indicating that this process is controlled first by a fibril-like mechanism and then by a spherulitic-type mechanism with an increasing heating rate.Additionally,the enthalpy change of MgV_(2)O_(6)at high temperatures was measured utilizing the drop calorimetry,heat capacity was calculated and given as:Cp=208.3+0.03583T-4809000T^(−2)(298-923 K)(J mol^(−1)K^(−1)),the high-temperature heat capacity can be used to calculate Gibbs free energy of MgV_(2)O_(6)at high temperatures.展开更多
A novel compound(H_(2)L)SCN(5⁃methyl⁃3⁃phenyl⁃2H⁃pyrazol⁃1⁃ium thiocyanate)has been obtained by the reaction of thiosemicarbazide with benzoylacetone in ethanol.Two zinccomplexes[Zn(HL)_(2)(NCS)(CH_(3)COO)](1)and[Zn_(...A novel compound(H_(2)L)SCN(5⁃methyl⁃3⁃phenyl⁃2H⁃pyrazol⁃1⁃ium thiocyanate)has been obtained by the reaction of thiosemicarbazide with benzoylacetone in ethanol.Two zinccomplexes[Zn(HL)_(2)(NCS)(CH_(3)COO)](1)and[Zn_(2)(L)_(2)(HL)_(2)(NCS)_(2)]_(2)·2CH_(3)OH(2)have been synthesized by the coordination reactions of Zn(OAc)_(2)·2H_(2)O or ZnCl_(2)with(H_(2)L)SCN under reflux conditions.Elemental analyses and single⁃crystal X⁃ray diffraction have con⁃firmed the structures of the synthesized compounds.The(H_(2)L)SCN ligand and complex 1 pertain to the triclinic sys⁃tem with space group P1,while complex 2 belongs to the monoclinic system with space group P2_(1)/n.Additionally,the antibacterial activities of the compounds were evaluated in vitro using the agar diffusion method against the bac⁃terial strains(Candida albicans,Staphylococcus aureus,and Escherichia coli).The results showed that the ligand exhibited relatively good antibacterial activities against the bacteria,and the complexes possessed stronger antibac⁃terial activities against the same bacteria than the free ligand.CCDC:2190252,(H2L)SCN;2190253,1;2190256,2.展开更多
Metal–organic frameworks(MOFs) are crystalline porous materials with tunable properties, exhibiting great potential in gas adsorption, separation and catalysis.[1,2]It is challenging to visualize MOFs with transmissi...Metal–organic frameworks(MOFs) are crystalline porous materials with tunable properties, exhibiting great potential in gas adsorption, separation and catalysis.[1,2]It is challenging to visualize MOFs with transmission electron microscopy(TEM) due to their inherent instability under electron beam irradiation. Here, we employ cryo-electron microscopy(cryoEM) to capture images of MOF ZIF-8, revealing inverted-space structural information at a resolution of up to about 1.7A and enhancing its critical electron dose to around 20 e^(-)/A^(2). In addition, it is confirmed by electron-beam irradiation experiments that the high voltage could effectively mitigate the radiolysis, and the structure of ZIF-8 is more stable along the [100] direction under electron beam irradiation. Meanwhile, since the high-resolution electron microscope images are modulated by contrast transfer function(CTF) and it is difficult to determine the positions corresponding to the atomic columns directly from the images. We employ image deconvolution to eliminate the impact of CTF and obtain the structural images of ZIF-8. As a result, the heavy atom Zn and the organic imidazole ring within the organic framework can be distinguished from structural images.展开更多
Two new coordination polymers,[Ni(Hpdc)(bib)(H_(2)O)]_(n)(1)and{[Ni(bib)_(3)](ClO_(4))_(2)}_(n)(2),were prepared by mixing Ni^(2+),3,5⁃pyrazoledicarboxylic acid(H3pdc)/p⁃nitrobenzoic acid and 1,4⁃bis(imidazol⁃1⁃ylmeth...Two new coordination polymers,[Ni(Hpdc)(bib)(H_(2)O)]_(n)(1)and{[Ni(bib)_(3)](ClO_(4))_(2)}_(n)(2),were prepared by mixing Ni^(2+),3,5⁃pyrazoledicarboxylic acid(H3pdc)/p⁃nitrobenzoic acid and 1,4⁃bis(imidazol⁃1⁃ylmethyl)butane(bib)by a hydrothermal method,respectively.X⁃ray crystallography reveals a 2D network constructed by six⁃coordinated Ni(Ⅱ)centers,bib,and Hpdc2-ligands in complex 1,while a 2D network is built by Ni(Ⅱ)and bib ligands in 2.Furthermore,the quantum⁃chemical calculations have been performed on‘molecular fragments’extracted from the crystal structure of 1 using the PBE0/LANL2DZ method in Gaussian 16 and the VASP program.CCDC:2343794,1;2343798,2.展开更多
Organic light-emitting diodes(OLEDs)have important applications in the field of next-generation displays and lighting,and phosphorescent iridium complexes are an important class of electroluminescent phosphorescent ma...Organic light-emitting diodes(OLEDs)have important applications in the field of next-generation displays and lighting,and phosphorescent iridium complexes are an important class of electroluminescent phosphorescent materials.In this paper,Ir(bmppy)_(3),tris(4-methyl-2,5-diphenylpyridine)iridium,was synthesized and elvaluted for photo-physical characteristics.Single crystals suitale for X-ray diffraction(XRD)were grown from a mixture solvent of dichloromethane and absolute ethanol.The composition and structur of Ir(bmppy)_(3)were determined by element analysis,NMR spectra and XRD.The complex crystallizes in the monoclinic symmetry with the space group P21/c with a slightly distorted octahedral configuration.As measured by UV-Visible and photoluminescence spectra,Ir(bmppy)_(3) displays a maximum emission at at 527 nm at ambient temperature,a typical green-emitting profile.The complex has potential for application in the OLED industry.展开更多
The crystal structure of CaSrFe<sub>0.75</sub>Co<sub>0.75</sub>Mn<sub>0.5</sub>O<sub>6−δ</sub> is investigated through neutron diffraction techniques in this study. The...The crystal structure of CaSrFe<sub>0.75</sub>Co<sub>0.75</sub>Mn<sub>0.5</sub>O<sub>6−δ</sub> is investigated through neutron diffraction techniques in this study. The material is synthesized using a solid-state synthesis method at a temperature of 1200˚C. Neutron diffraction data is subjected to Rietveld refinement, and a comparative analysis with X-ray diffraction (XRD) data is performed to unravel the structural details of the material. The findings reveal that the synthesized material exhibits a cubic crystal structure with a Pm-3m phase. The neutron diffraction results offer valuable insights into the arrangement of atoms within the lattice, contributing to a comprehensive understanding of the material’s structural properties. This research enhances our knowledge of CaSrFe0.75</sub>Co0.75</sub>Mn0.5</sub>O6−δ</sub>, with potential implications for its applications in various technological and scientific domains.展开更多
In the traditional process, m-phenylenediamine reacts with fuming sulfuric acid at high temperature to get intermediates, and then after dehydration occurs intramolecular rearrangement to get 2,4-diaminobenzenesulfoni...In the traditional process, m-phenylenediamine reacts with fuming sulfuric acid at high temperature to get intermediates, and then after dehydration occurs intramolecular rearrangement to get 2,4-diaminobenzenesulfonic acid. Traditional methods need to consume a lot of fuming sulfuric acid or concentrated sulfuric acid, resulting in high industrial large-scale production cost, more waste, and posing a serious environmental pollution risk. In this thesis, three different sulfonation reagents were used for the sulfonation reaction of m-phenylenediamine, and the reaction mechanisms and crystal structures of the three pathways were investigated. The three routes are: 1) one-step synthesis of monosulfonated compound 1 from raw material and sulfur trioxide (SO<sub>3</sub>);2) rapid reaction of raw material and chlorosulfonic acid to synthesize bisulfonated compound 2;3) direct eutectic crystallization of raw material and ordinary sulfuric acid to obtain compound 3. The crystal structure of the compounds synthesized by three paths was analyzed by X-ray single crystal diffraction, and compound 1 was characterized by NMR, Fourier infrared spectra, UV-visible spectrum and Mass spectrometry. The one-step synthesis of SO<sub>3</sub> as a sulfonation reagent has the advantages of mild reaction conditions, simple operation and low cost.展开更多
Multifunctional photodetectors boost the development of traditional optical communication technology and emerging artificial intelligence fields, such as robotics and autonomous driving. However, the current implement...Multifunctional photodetectors boost the development of traditional optical communication technology and emerging artificial intelligence fields, such as robotics and autonomous driving. However, the current implementation of multifunctional detectors is based on the physical combination of optical lenses, gratings, and multiple photodetectors, the large size and its complex structure hinder the miniaturization, lightweight, and integration of devices. In contrast, perovskite materials have achieved remarkable progress in the field of multifunctional photodetectors due to their diverse crystal structures, simple morphology manipulation, and excellent optoelectronic properties. In this review, we first overview the crystal structures and morphology manipulation techniques of perovskite materials and then summarize the working mechanism and performance parameters of multifunctional photodetectors. Furthermore, the fabrication strategies of multifunctional perovskite photodetectors and their advancements are highlighted, including polarized light detection, spectral detection, angle-sensing detection, and selfpowered detection. Finally, the existing problems of multifunctional detectors and the perspectives of their future development are presented.展开更多
A new ternary compound,Mg_(11-x)Zn_(x)Sr in the Mg-Zn-Sr system was observed and studied using Scanning Electron Microscopy(SEM),Energy-Dispersive Spectroscope(EDS),X-Ray Diffraction(XRD)and Transmission Electron Micr...A new ternary compound,Mg_(11-x)Zn_(x)Sr in the Mg-Zn-Sr system was observed and studied using Scanning Electron Microscopy(SEM),Energy-Dispersive Spectroscope(EDS),X-Ray Diffraction(XRD)and Transmission Electron Microscopy(TEM).The XRD patterns were refined by the Rietveld refinement method and the results revealed that the crystallized Mg_(11-x)Zn_(x)Sr phase belonged to tetragonal I41/amd space group and had the Cd_(11)Ba prototype.The Mg atoms were successfully doped into Zn_(11)Sr crystal lattice by occupying Zn atomic sites.Moreover,the Rietveld refinement and computational results demonstrated a gradual decrease in the a-axis and c-axis lattice parameters with decreasing concentration levels of Mg coordination substitution in the lattice of Mg_(11-x)Zn_(x)Sr compound.The elastic constants and modulus of the Mg_(11-x)Zn_(x)Sr compounds calculated by first-principles calculations(FPC)indicated they were increased with the increasing of Zn content.The variation of hardness,D-band widths and the total density of states for Mg_(11-x)Zn_(x)Sr compounds with Zn content was discussed.展开更多
Based on the results of electron probe microanalysis(EPMA)and X-ray diffraction(XRD),the isothermal sections of Zr-Ni-Ge ternary system at 973 K and 1173 K were constructed through alloy sampling approach.It is worth ...Based on the results of electron probe microanalysis(EPMA)and X-ray diffraction(XRD),the isothermal sections of Zr-Ni-Ge ternary system at 973 K and 1173 K were constructed through alloy sampling approach.It is worth noting that the crystallographic information of the formerly reportedτ2(Zr_(0.98)NiGe_(2.94))was determined,which belongs to the space group Pbcm(No.57).Besides the formerly reported ternary compounds,τ1(Zr_(6)Ni_(16)Ge_(7)),τ_(2)(Zr_(0.98)NiGe_(2.94)),τ_(3)(Zr_(3)Ni_(4)Ge_(4)),τ_(4)(ZrNiGe)andτ_(5)(Zr_(2)Ni_(0.54)Ge_(0.46)),a new ternary phase namedτ_(6)with the composition of Zr_(39)Ni_(18)Ge_(43)was primarily detected in this work.In addition,an invariant reaction Ni_(5)Ge_(3)+τ_(4)τ_(1)+τ_(3)between 973 K and 1173 K was deduced.展开更多
New solid complex of the antimony trichloride and dioxane was obtained th rough a reaction of the dioxane and the absolute methanol solution of the antimony trichloride.The formula of the complex is[SbCl_(3)·{(CH...New solid complex of the antimony trichloride and dioxane was obtained th rough a reaction of the dioxane and the absolute methanol solution of the antimony trichloride.The formula of the complex is[SbCl_(3)·{(CH_(2))_(4)O_(2)}_(1.5)].The crystal structure of the comple x belongs to cubic system,space group I-43d,a=17.1417(5)?,Z=16.The trivalent antimony ion not only bonds directly to three chlorine anions,but also is co ordinated by three oxygen atoms of th e dioxane molecules.Two oxygen atoms in a dioxane molecule wi ll coordinate to different antimony ions,respectively.展开更多
Nanoscale Sb doped titanium dioxide thin films photocatalyst （Ti1-xSbO2） were obtained from dip-coating sol-gel method. The influence of dopant Sb density on the crystal structure and the phase transformation of the...Nanoscale Sb doped titanium dioxide thin films photocatalyst （Ti1-xSbO2） were obtained from dip-coating sol-gel method. The influence of dopant Sb density on the crystal structure and the phase transformation of the thin tilms were characterized by X-ray diffraction （XRD） and Raman spectra. The results of XRD showed that as prepared lilms were not only in anatase state but also in brookite. The crystalline size was estimated to be around 13.3-20 nm. Raman spectra indicated there coexisted other phases and a transformation from brookite to anatase in the samples doped with 0.2% Sb. After doping a proper amount of Sb, the cryst,allization rate and the content of the anatase Ti1-x, SbO2 in the thin films was clearly enhanced because Sb replaced part. of the Ti of TiO2 in the thin films. The anode current density （photocurrent density） and the first order reaction speed constant （k） of t.hin films doped with 0.2% Sb reached 42.49 μA/cm^2 and 0.171 h/cm^2 under 254 nm UV illumination, respectively, which is about 11 times and 2 times that of the non doped TiO2 anode prepared by the same method respectively.展开更多
An aminophenol ligand, N,N,N＇-tri（2-hydroxy-5-methylbenzyl）-l,2-ethanediamine, was prepared through the Marmich reaction, and structurally characterized by NMR, IR, MS and single-crystal X-ray diffraction. The titl...An aminophenol ligand, N,N,N＇-tri（2-hydroxy-5-methylbenzyl）-l,2-ethanediamine, was prepared through the Marmich reaction, and structurally characterized by NMR, IR, MS and single-crystal X-ray diffraction. The title compound （C26H32N2O3, Mr = 420.54） belongs to the monoclinic system, space group P21/n with a = 8.6233（14）, b = 10.2655（16）, c = 26.017（4） A, β = 95.797（2）°, V = 2291.3（6） A^3, Z = 4, the final R = 0.0461 and wR = 0.1139 for 4267 unique reflections （Rint = 0.028） with 11691 observed ones （I〉 2a（I））.展开更多
A novel compound Cu（phen）（m-CBA）2 was synthesized with m-chlorobenzoic acid（m-CBA）, 1,10-phenanthroline（phen） and Cu（OAc）2·H2O. It was characterized by IR, UV, elemental analyses and X-ray crystallograp...A novel compound Cu（phen）（m-CBA）2 was synthesized with m-chlorobenzoic acid（m-CBA）, 1,10-phenanthroline（phen） and Cu（OAc）2·H2O. It was characterized by IR, UV, elemental analyses and X-ray crystallography. It crystallizes in the monoclinic crystal system with C2/c space group, a=2.9699（4） nm, b=1.15452（2） nm, c=1.5335（2） nm, β=111.118（2）°, V=4.905 1（1） nm3, Z=8, F（000）=2 328, R1=0.072 8, wR2=0.223 4 [I2σ（I）]. Structure analysis shows that the copper center coordinates with two nitrogen atoms from one 1,10-phenanthroline molecule, two oxygen atoms from two m-chlorobenzoic acid molecules, giving a distorted squared planar coordination geometry. This novel compound shows paramagnetic interactions between copper centers.展开更多
Antofloxacin free base is prepared from antofloxacin hydrochloride by removing hydrogen chloride. Its crystal is obtained by slow evaporation of an acetonitrile-methanol mixed solution. Single-crystal X-ray diffractio...Antofloxacin free base is prepared from antofloxacin hydrochloride by removing hydrogen chloride. Its crystal is obtained by slow evaporation of an acetonitrile-methanol mixed solution. Single-crystal X-ray diffraction reveals that the crystallography belongs to a triclinic PI space group with cell parameters： a = 0. 663 07（13） nm, b = 0. 898 39（18） nm, c = 1. 569 0（3） nm, α = 75.12（3）°,β = 87.92（3）°, γ = 77.57 （3）°. Antofloxacin shows no fluorescence in solution, but the crystalline state emits strong green light at 510 nm under the excitation of 360 nm, indicating a fluorescence enhancement induced by aggregation. It demonstrates that intermolecular packing and interaction in the crystal lead to the improved fluorescence quantum yield. These results provide important intbrmation for the further exploration of the structure-activity relationship of antofloxacin and the development of new drugs.展开更多
To make inorganic structure data more useful for further studies a five-point list of simple procedures to be followed by authors of crystal structure papers is proposed. 1. A crystal structure should be described wit...To make inorganic structure data more useful for further studies a five-point list of simple procedures to be followed by authors of crystal structure papers is proposed. 1. A crystal structure should be described with the space group corresponding to its true symmetry. 2. A new structure proposal should be tested, if it is realistic in principle. 3. A structure should be described with a space group in a setting given in the International Tables. 4. For a comparison with other structures the structure data should be standardized with the program STRUCTURE TIDY. 5. 揘ew?structure data should be checked in the databases, Chemical Abstracts or on-line internet resources, if they are really new. The list is supplemented with many explanations, commentaries, examples and references.展开更多
The crystat structure of {[Er;（L—Glu）;（H;O）;]（ClO;）;·3H;O);has been studied by X-ray diffraction. The crystal is monoctinic with space group P2;and cell parameters a=19.987（3） , b=16.505（3） , c=11.040...The crystat structure of {[Er;（L—Glu）;（H;O）;]（ClO;）;·3H;O);has been studied by X-ray diffraction. The crystal is monoctinic with space group P2;and cell parameters a=19.987（3） , b=16.505（3） , c=11.040（2） , β=104.69（1）;, V=3538（1） , Z=2, Dc=2.29 g. cm;, μ=53.2 cm;, F（000）=2384. The asymmetric unit contains two complex motecules and four centre ions. Each erbium （Ⅲ） is coordinated by five oxygen donors from four different glutamates and four oxygen donors from the aqua ligand to form a nine coordination potyhedron. The mean distances of Er—0 （carboxylate） and Er—Ow are 2.439 and 2.41 respectivety. The finat R and Rw are 0.043 and 0. 058, respectivety.展开更多
Pyrrhotite is an associated mineral that exists widely in sulfide ore. The presence of pyrrhotite will affect the recovery of platinum group minerals. Therefore, researchers have paid increasing attention to the flota...Pyrrhotite is an associated mineral that exists widely in sulfide ore. The presence of pyrrhotite will affect the recovery of platinum group minerals. Therefore, researchers have paid increasing attention to the flotation separation of pyrrhotite. Pyrrhotite superstructures owning different Fe/S ratios results in various crystal structures, corresponding to different physical, chemical and electronic properties, and consequently different flotation behavior. In the present paper, a comprehensive review is conducted to discuss the influence of crystal structures on the natural floatability, mineral-reagent interaction, surface oxidation and flotation electrochemistry of pyrrhotite. The selective flotation process of pyrrhotite from its associated minerals is also reviewed in this paper. It is hoped that this review can summarize the newly published research results combined with some representative results from the past, to provide a theoretical basis for the study of the flotation mechanism of pyrrhotite and provide a new direction for future research on pyrrhotite.展开更多
The Schiff base, 2-{（2′-benzyl）iminoethyl}-5-methoxyphenol （C6H4CH2N=C（CH3）C6H3- （OMe-5）OH） 1, was synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The compound cr...The Schiff base, 2-{（2′-benzyl）iminoethyl}-5-methoxyphenol （C6H4CH2N=C（CH3）C6H3- （OMe-5）OH） 1, was synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The compound crystallizes in the orthorhombic system, space group Pbca with a = 8.9849（10）, b = 13.2699（15）, c = 22.975（2） A ,V= 2739.3（5） A^3, Mr= 255.31, Z= 8, F（000） = 1088, Dc = 1.238 g/cm^3, T= 293 K, μ = 0.082 mm^-1, λ = 0.71073 .A, the final R = 0.0596 and wR = 0.1575 for 1934 observed reflections with I 〉 2σ（I）. The complex was valued for its antimicrobial activity against bacterial strands using the agar diffusion method, and found to be active against the four test bacterial organisms.展开更多
The absorption, fluorescence and Raman spectra of Ce(NO3)(3)(phen)(2) complex were assigned and the crystal structure of the complex was studied. Meanwhile the interactions between Cc (NO3)(3) (phen)(2) and DNA were s...The absorption, fluorescence and Raman spectra of Ce(NO3)(3)(phen)(2) complex were assigned and the crystal structure of the complex was studied. Meanwhile the interactions between Cc (NO3)(3) (phen)(2) and DNA were studied by spectrum methods. As DNA was added, it is found that both the UV absorption bands of Ce(NO3)(3)(phen)(2) and the SERS bands of Ce(NO3)(3)(phen)(2) weaken evidently, while the fluorescence intensity of Ce(NO3)(3)(phen)(2) enhance dramatically. The complex compete against EB on the reaction with DNA. It is indicated by this spectrum methods that there are strong interactions between Ce(NO3)(3)(phen)(2) and DNA, and the bond mode is intercalation. The bond constant of the complex with DNA is determined to be 1.7 x 10(5).展开更多
基金supported by the National Key R&D Program of China(2018YFC1900500)the Graduate Scientific Research and Innovation Foundation of Chongqing,China(Grant No.CYB20002).
文摘As a promising anode material for magnesium ion rechargeable batteries,magnesium metavanadate(MgV_(2)O_(6))has attracted considerable research interest in recent years.A MgV_(2)O_(6)sample was synthesized via a facile solid-state reaction by multistep-firing stoichiometric mixtures of MgO and V2O5 powder under an air atmosphere.The solid-state phase transition fromα-MgV_(2)O_(6)toβ-MgV_(2)O_(6)occurred at 841 K and the enthalpy change was 4.37±0.04 kJ/mol.The endothermic effect at 1014 K and the enthalpy change was 26.54±0.26 kJ/mol,which is related to the incongruent melting ofβ-MgV_(2)O_(6).In situ XRD was performed to investigate phase transition of the as-prepared MgV_(2)O_(6)at high temperatures.The cell parameters obtained by Rietveld refinement indicated that it crystallizes in a monoclinic system with the C2/m space group,and the lattice parameters of a=9.280 A°,b=3.501 A°,c=6.731 A°,β=111.76°.The solid-state phase transition fromα-MgV_(2)O_(6)toβ-MgV_(2)O_(6)was further studied by thermal kinetics,indicating that this process is controlled first by a fibril-like mechanism and then by a spherulitic-type mechanism with an increasing heating rate.Additionally,the enthalpy change of MgV_(2)O_(6)at high temperatures was measured utilizing the drop calorimetry,heat capacity was calculated and given as:Cp=208.3+0.03583T-4809000T^(−2)(298-923 K)(J mol^(−1)K^(−1)),the high-temperature heat capacity can be used to calculate Gibbs free energy of MgV_(2)O_(6)at high temperatures.
文摘A novel compound(H_(2)L)SCN(5⁃methyl⁃3⁃phenyl⁃2H⁃pyrazol⁃1⁃ium thiocyanate)has been obtained by the reaction of thiosemicarbazide with benzoylacetone in ethanol.Two zinccomplexes[Zn(HL)_(2)(NCS)(CH_(3)COO)](1)and[Zn_(2)(L)_(2)(HL)_(2)(NCS)_(2)]_(2)·2CH_(3)OH(2)have been synthesized by the coordination reactions of Zn(OAc)_(2)·2H_(2)O or ZnCl_(2)with(H_(2)L)SCN under reflux conditions.Elemental analyses and single⁃crystal X⁃ray diffraction have con⁃firmed the structures of the synthesized compounds.The(H_(2)L)SCN ligand and complex 1 pertain to the triclinic sys⁃tem with space group P1,while complex 2 belongs to the monoclinic system with space group P2_(1)/n.Additionally,the antibacterial activities of the compounds were evaluated in vitro using the agar diffusion method against the bac⁃terial strains(Candida albicans,Staphylococcus aureus,and Escherichia coli).The results showed that the ligand exhibited relatively good antibacterial activities against the bacteria,and the complexes possessed stronger antibac⁃terial activities against the same bacteria than the free ligand.CCDC:2190252,(H2L)SCN;2190253,1;2190256,2.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12074409 and 12374021)。
文摘Metal–organic frameworks(MOFs) are crystalline porous materials with tunable properties, exhibiting great potential in gas adsorption, separation and catalysis.[1,2]It is challenging to visualize MOFs with transmission electron microscopy(TEM) due to their inherent instability under electron beam irradiation. Here, we employ cryo-electron microscopy(cryoEM) to capture images of MOF ZIF-8, revealing inverted-space structural information at a resolution of up to about 1.7A and enhancing its critical electron dose to around 20 e^(-)/A^(2). In addition, it is confirmed by electron-beam irradiation experiments that the high voltage could effectively mitigate the radiolysis, and the structure of ZIF-8 is more stable along the [100] direction under electron beam irradiation. Meanwhile, since the high-resolution electron microscope images are modulated by contrast transfer function(CTF) and it is difficult to determine the positions corresponding to the atomic columns directly from the images. We employ image deconvolution to eliminate the impact of CTF and obtain the structural images of ZIF-8. As a result, the heavy atom Zn and the organic imidazole ring within the organic framework can be distinguished from structural images.
文摘Two new coordination polymers,[Ni(Hpdc)(bib)(H_(2)O)]_(n)(1)and{[Ni(bib)_(3)](ClO_(4))_(2)}_(n)(2),were prepared by mixing Ni^(2+),3,5⁃pyrazoledicarboxylic acid(H3pdc)/p⁃nitrobenzoic acid and 1,4⁃bis(imidazol⁃1⁃ylmethyl)butane(bib)by a hydrothermal method,respectively.X⁃ray crystallography reveals a 2D network constructed by six⁃coordinated Ni(Ⅱ)centers,bib,and Hpdc2-ligands in complex 1,while a 2D network is built by Ni(Ⅱ)and bib ligands in 2.Furthermore,the quantum⁃chemical calculations have been performed on‘molecular fragments’extracted from the crystal structure of 1 using the PBE0/LANL2DZ method in Gaussian 16 and the VASP program.CCDC:2343794,1;2343798,2.
文摘Organic light-emitting diodes(OLEDs)have important applications in the field of next-generation displays and lighting,and phosphorescent iridium complexes are an important class of electroluminescent phosphorescent materials.In this paper,Ir(bmppy)_(3),tris(4-methyl-2,5-diphenylpyridine)iridium,was synthesized and elvaluted for photo-physical characteristics.Single crystals suitale for X-ray diffraction(XRD)were grown from a mixture solvent of dichloromethane and absolute ethanol.The composition and structur of Ir(bmppy)_(3)were determined by element analysis,NMR spectra and XRD.The complex crystallizes in the monoclinic symmetry with the space group P21/c with a slightly distorted octahedral configuration.As measured by UV-Visible and photoluminescence spectra,Ir(bmppy)_(3) displays a maximum emission at at 527 nm at ambient temperature,a typical green-emitting profile.The complex has potential for application in the OLED industry.
文摘The crystal structure of CaSrFe<sub>0.75</sub>Co<sub>0.75</sub>Mn<sub>0.5</sub>O<sub>6−δ</sub> is investigated through neutron diffraction techniques in this study. The material is synthesized using a solid-state synthesis method at a temperature of 1200˚C. Neutron diffraction data is subjected to Rietveld refinement, and a comparative analysis with X-ray diffraction (XRD) data is performed to unravel the structural details of the material. The findings reveal that the synthesized material exhibits a cubic crystal structure with a Pm-3m phase. The neutron diffraction results offer valuable insights into the arrangement of atoms within the lattice, contributing to a comprehensive understanding of the material’s structural properties. This research enhances our knowledge of CaSrFe0.75</sub>Co0.75</sub>Mn0.5</sub>O6−δ</sub>, with potential implications for its applications in various technological and scientific domains.
文摘In the traditional process, m-phenylenediamine reacts with fuming sulfuric acid at high temperature to get intermediates, and then after dehydration occurs intramolecular rearrangement to get 2,4-diaminobenzenesulfonic acid. Traditional methods need to consume a lot of fuming sulfuric acid or concentrated sulfuric acid, resulting in high industrial large-scale production cost, more waste, and posing a serious environmental pollution risk. In this thesis, three different sulfonation reagents were used for the sulfonation reaction of m-phenylenediamine, and the reaction mechanisms and crystal structures of the three pathways were investigated. The three routes are: 1) one-step synthesis of monosulfonated compound 1 from raw material and sulfur trioxide (SO<sub>3</sub>);2) rapid reaction of raw material and chlorosulfonic acid to synthesize bisulfonated compound 2;3) direct eutectic crystallization of raw material and ordinary sulfuric acid to obtain compound 3. The crystal structure of the compounds synthesized by three paths was analyzed by X-ray single crystal diffraction, and compound 1 was characterized by NMR, Fourier infrared spectra, UV-visible spectrum and Mass spectrometry. The one-step synthesis of SO<sub>3</sub> as a sulfonation reagent has the advantages of mild reaction conditions, simple operation and low cost.
基金supported financially by the National Key R&D Program of China (Nos. 2018YFA0208501 and 2018YFA0703200)the National Natural Science Foundation of China (NSFC, Nos. 52103236, 91963212, 21875260)Beijing National Laboratory for Molecular Sciences (No. BNLMSCXXM-202005)。
文摘Multifunctional photodetectors boost the development of traditional optical communication technology and emerging artificial intelligence fields, such as robotics and autonomous driving. However, the current implementation of multifunctional detectors is based on the physical combination of optical lenses, gratings, and multiple photodetectors, the large size and its complex structure hinder the miniaturization, lightweight, and integration of devices. In contrast, perovskite materials have achieved remarkable progress in the field of multifunctional photodetectors due to their diverse crystal structures, simple morphology manipulation, and excellent optoelectronic properties. In this review, we first overview the crystal structures and morphology manipulation techniques of perovskite materials and then summarize the working mechanism and performance parameters of multifunctional photodetectors. Furthermore, the fabrication strategies of multifunctional perovskite photodetectors and their advancements are highlighted, including polarized light detection, spectral detection, angle-sensing detection, and selfpowered detection. Finally, the existing problems of multifunctional detectors and the perspectives of their future development are presented.
基金the National Key Research and Development Program of China(grant numbers 2018YFC1106702)the Natural Science Foundation of Guangdong Province,China(grant numbers 2020A1515011301,2018A0303100018 and 2018A030313950)+1 种基金Shenzhen Basic Research Project(grant numbers JCYJ20170815153143221,JCYJ20200109144608205 and JCYJ20170815153210359)IER Foundation(HT-JD-CXY-201902 and HT-JD-CXY201907)for financial support
文摘A new ternary compound,Mg_(11-x)Zn_(x)Sr in the Mg-Zn-Sr system was observed and studied using Scanning Electron Microscopy(SEM),Energy-Dispersive Spectroscope(EDS),X-Ray Diffraction(XRD)and Transmission Electron Microscopy(TEM).The XRD patterns were refined by the Rietveld refinement method and the results revealed that the crystallized Mg_(11-x)Zn_(x)Sr phase belonged to tetragonal I41/amd space group and had the Cd_(11)Ba prototype.The Mg atoms were successfully doped into Zn_(11)Sr crystal lattice by occupying Zn atomic sites.Moreover,the Rietveld refinement and computational results demonstrated a gradual decrease in the a-axis and c-axis lattice parameters with decreasing concentration levels of Mg coordination substitution in the lattice of Mg_(11-x)Zn_(x)Sr compound.The elastic constants and modulus of the Mg_(11-x)Zn_(x)Sr compounds calculated by first-principles calculations(FPC)indicated they were increased with the increasing of Zn content.The variation of hardness,D-band widths and the total density of states for Mg_(11-x)Zn_(x)Sr compounds with Zn content was discussed.
基金Sponsored by the Major State Basic Research Development Program of China(Grant No.2014CB6644002).
文摘Based on the results of electron probe microanalysis(EPMA)and X-ray diffraction(XRD),the isothermal sections of Zr-Ni-Ge ternary system at 973 K and 1173 K were constructed through alloy sampling approach.It is worth noting that the crystallographic information of the formerly reportedτ2(Zr_(0.98)NiGe_(2.94))was determined,which belongs to the space group Pbcm(No.57).Besides the formerly reported ternary compounds,τ1(Zr_(6)Ni_(16)Ge_(7)),τ_(2)(Zr_(0.98)NiGe_(2.94)),τ_(3)(Zr_(3)Ni_(4)Ge_(4)),τ_(4)(ZrNiGe)andτ_(5)(Zr_(2)Ni_(0.54)Ge_(0.46)),a new ternary phase namedτ_(6)with the composition of Zr_(39)Ni_(18)Ge_(43)was primarily detected in this work.In addition,an invariant reaction Ni_(5)Ge_(3)+τ_(4)τ_(1)+τ_(3)between 973 K and 1173 K was deduced.
文摘New solid complex of the antimony trichloride and dioxane was obtained th rough a reaction of the dioxane and the absolute methanol solution of the antimony trichloride.The formula of the complex is[SbCl_(3)·{(CH_(2))_(4)O_(2)}_(1.5)].The crystal structure of the comple x belongs to cubic system,space group I-43d,a=17.1417(5)?,Z=16.The trivalent antimony ion not only bonds directly to three chlorine anions,but also is co ordinated by three oxygen atoms of th e dioxane molecules.Two oxygen atoms in a dioxane molecule wi ll coordinate to different antimony ions,respectively.
文摘Nanoscale Sb doped titanium dioxide thin films photocatalyst （Ti1-xSbO2） were obtained from dip-coating sol-gel method. The influence of dopant Sb density on the crystal structure and the phase transformation of the thin tilms were characterized by X-ray diffraction （XRD） and Raman spectra. The results of XRD showed that as prepared lilms were not only in anatase state but also in brookite. The crystalline size was estimated to be around 13.3-20 nm. Raman spectra indicated there coexisted other phases and a transformation from brookite to anatase in the samples doped with 0.2% Sb. After doping a proper amount of Sb, the cryst,allization rate and the content of the anatase Ti1-x, SbO2 in the thin films was clearly enhanced because Sb replaced part. of the Ti of TiO2 in the thin films. The anode current density （photocurrent density） and the first order reaction speed constant （k） of t.hin films doped with 0.2% Sb reached 42.49 μA/cm^2 and 0.171 h/cm^2 under 254 nm UV illumination, respectively, which is about 11 times and 2 times that of the non doped TiO2 anode prepared by the same method respectively.
基金supported by Shandong Province Higher Educational Science and Technology Program (J09LB03)
文摘An aminophenol ligand, N,N,N＇-tri（2-hydroxy-5-methylbenzyl）-l,2-ethanediamine, was prepared through the Marmich reaction, and structurally characterized by NMR, IR, MS and single-crystal X-ray diffraction. The title compound （C26H32N2O3, Mr = 420.54） belongs to the monoclinic system, space group P21/n with a = 8.6233（14）, b = 10.2655（16）, c = 26.017（4） A, β = 95.797（2）°, V = 2291.3（6） A^3, Z = 4, the final R = 0.0461 and wR = 0.1139 for 4267 unique reflections （Rint = 0.028） with 11691 observed ones （I〉 2a（I））.
基金Project (21001118) supported by the National Natural Science Foundation of China
文摘A novel compound Cu（phen）（m-CBA）2 was synthesized with m-chlorobenzoic acid（m-CBA）, 1,10-phenanthroline（phen） and Cu（OAc）2·H2O. It was characterized by IR, UV, elemental analyses and X-ray crystallography. It crystallizes in the monoclinic crystal system with C2/c space group, a=2.9699（4） nm, b=1.15452（2） nm, c=1.5335（2） nm, β=111.118（2）°, V=4.905 1（1） nm3, Z=8, F（000）=2 328, R1=0.072 8, wR2=0.223 4 [I2σ（I）]. Structure analysis shows that the copper center coordinates with two nitrogen atoms from one 1,10-phenanthroline molecule, two oxygen atoms from two m-chlorobenzoic acid molecules, giving a distorted squared planar coordination geometry. This novel compound shows paramagnetic interactions between copper centers.
文摘Antofloxacin free base is prepared from antofloxacin hydrochloride by removing hydrogen chloride. Its crystal is obtained by slow evaporation of an acetonitrile-methanol mixed solution. Single-crystal X-ray diffraction reveals that the crystallography belongs to a triclinic PI space group with cell parameters： a = 0. 663 07（13） nm, b = 0. 898 39（18） nm, c = 1. 569 0（3） nm, α = 75.12（3）°,β = 87.92（3）°, γ = 77.57 （3）°. Antofloxacin shows no fluorescence in solution, but the crystalline state emits strong green light at 510 nm under the excitation of 360 nm, indicating a fluorescence enhancement induced by aggregation. It demonstrates that intermolecular packing and interaction in the crystal lead to the improved fluorescence quantum yield. These results provide important intbrmation for the further exploration of the structure-activity relationship of antofloxacin and the development of new drugs.
文摘To make inorganic structure data more useful for further studies a five-point list of simple procedures to be followed by authors of crystal structure papers is proposed. 1. A crystal structure should be described with the space group corresponding to its true symmetry. 2. A new structure proposal should be tested, if it is realistic in principle. 3. A structure should be described with a space group in a setting given in the International Tables. 4. For a comparison with other structures the structure data should be standardized with the program STRUCTURE TIDY. 5. 揘ew?structure data should be checked in the databases, Chemical Abstracts or on-line internet resources, if they are really new. The list is supplemented with many explanations, commentaries, examples and references.
文摘The crystat structure of {[Er;（L—Glu）;（H;O）;]（ClO;）;·3H;O);has been studied by X-ray diffraction. The crystal is monoctinic with space group P2;and cell parameters a=19.987（3） , b=16.505（3） , c=11.040（2） , β=104.69（1）;, V=3538（1） , Z=2, Dc=2.29 g. cm;, μ=53.2 cm;, F（000）=2384. The asymmetric unit contains two complex motecules and four centre ions. Each erbium （Ⅲ） is coordinated by five oxygen donors from four different glutamates and four oxygen donors from the aqua ligand to form a nine coordination potyhedron. The mean distances of Er—0 （carboxylate） and Er—Ow are 2.439 and 2.41 respectivety. The finat R and Rw are 0.043 and 0. 058, respectivety.
基金supported by National Natural Science Foundation of China (NSFC52174246,NSFC51864003)Guangxi Natural Science Foundation (2018GXNSFAA050127)。
文摘Pyrrhotite is an associated mineral that exists widely in sulfide ore. The presence of pyrrhotite will affect the recovery of platinum group minerals. Therefore, researchers have paid increasing attention to the flotation separation of pyrrhotite. Pyrrhotite superstructures owning different Fe/S ratios results in various crystal structures, corresponding to different physical, chemical and electronic properties, and consequently different flotation behavior. In the present paper, a comprehensive review is conducted to discuss the influence of crystal structures on the natural floatability, mineral-reagent interaction, surface oxidation and flotation electrochemistry of pyrrhotite. The selective flotation process of pyrrhotite from its associated minerals is also reviewed in this paper. It is hoped that this review can summarize the newly published research results combined with some representative results from the past, to provide a theoretical basis for the study of the flotation mechanism of pyrrhotite and provide a new direction for future research on pyrrhotite.
基金This work was supported by the Key Laboratory of Marine Biotechnology of Jiangsu Province
文摘The Schiff base, 2-{（2′-benzyl）iminoethyl}-5-methoxyphenol （C6H4CH2N=C（CH3）C6H3- （OMe-5）OH） 1, was synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The compound crystallizes in the orthorhombic system, space group Pbca with a = 8.9849（10）, b = 13.2699（15）, c = 22.975（2） A ,V= 2739.3（5） A^3, Mr= 255.31, Z= 8, F（000） = 1088, Dc = 1.238 g/cm^3, T= 293 K, μ = 0.082 mm^-1, λ = 0.71073 .A, the final R = 0.0596 and wR = 0.1575 for 1934 observed reflections with I 〉 2σ（I）. The complex was valued for its antimicrobial activity against bacterial strands using the agar diffusion method, and found to be active against the four test bacterial organisms.
文摘The absorption, fluorescence and Raman spectra of Ce(NO3)(3)(phen)(2) complex were assigned and the crystal structure of the complex was studied. Meanwhile the interactions between Cc (NO3)(3) (phen)(2) and DNA were studied by spectrum methods. As DNA was added, it is found that both the UV absorption bands of Ce(NO3)(3)(phen)(2) and the SERS bands of Ce(NO3)(3)(phen)(2) weaken evidently, while the fluorescence intensity of Ce(NO3)(3)(phen)(2) enhance dramatically. The complex compete against EB on the reaction with DNA. It is indicated by this spectrum methods that there are strong interactions between Ce(NO3)(3)(phen)(2) and DNA, and the bond mode is intercalation. The bond constant of the complex with DNA is determined to be 1.7 x 10(5).
