Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been construc...Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been constructed hydrothermally at 160℃ using H_(3)tpta([1,1':3',1″-terphenyl]-4,4',5'-tricarboxylic acid),py(pyridine),H_(2)biim(2,2'-biimidazole),dpe(1,2-di(4-pyridyl)ethylene),and zinc,nickel and cadmium chlorides,resulting in the formation of stable crystalline solids which were subsequently analyzed using infrared spectroscopy,element analysis,thermogravimetric analysis,as well as structural analyses conducted via single-crystal X-ray diffraction.The findings from these single-crystal Xray diffraction studies indicate that complexes 1-3 form crystals within the monoclinic system P2_(1)/c space group(1)or triclinic system P1 space group(2 and 3),and possess 1D,0D,and 3D structures,respectively.Complex 1 demonstrated substantial catalytic efficiency and excellent reusability as a heterogeneous catalyst in the reaction of Knoevenagel condensation under ambient temperature conditions.In addition,complex 1 also showcased notable anti-wear performance when used in polyalphaolefin synthetic lubricants.CCDC:2449810,1;2449811,2;2449812,3.展开更多
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'...Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6.展开更多
The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when th...The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when the cations are the same and the anions are different,in complex 1,Na^(+)closes one port of CyB5Q[5]through Na—O seven coordination bonds to form a molecular bowl;in complex 3,Na^(+)completely closes the two ports of CyB5Q[5]to form a molecular capsule with six Na—O coordination bonds;in complexes 2 and 4,the two ports of CyB5Q[5]are completely closed to form K—O coordinated molecular capsules,but the K^(+)of complex 2 is six-coordinated and that of complex 4 is eight-/nine-coordinated.and complex 4 are connected by three oxygen bridges to form a 1D molecular chain.CCDC:2457122,1;2457121,2;2457400,3;2457120,4.展开更多
Charge-transfer complexes(CTCs)have emerged as promising n-type organic thermoelectric(TE)materials due to their inherent high electrical conductivity and tunable transport polarities.In this study,we performed a comp...Charge-transfer complexes(CTCs)have emerged as promising n-type organic thermoelectric(TE)materials due to their inherent high electrical conductivity and tunable transport polarities.In this study,we performed a comprehensive first-principles investigation on the TE properties of nine CTCs comprised of 2,7-dialkyl[1]benzothieno[3,2-b][1]benzothiophenes(CnBTBT,n=4,8,12)as donors and fluorinated derivatives of tetracyanoquinodimethane(F_(m)TCNQ,m=0,2,4)as acceptors,aiming to identify high-performance n-type organic TE materials and elucidate the underlying structure-property relationships.Our calculation results,based on the Boltzmann transport equation and deformation potential theory,reveal that the length of the alkyl side chains and the number of fluorine substitutions significantly impact their electronic structures and TE properties.Notably,the CnBTBT-F_(m)TCNQ CTCs with shorter alkyl chains and more fluorine substitution demonstrate superior n-type characteristics,particularly C4BTBT-F4TCNQ,which achieves an excellent power factor of 671µW cm^(-1) K^(-2) at an optimal charge carrier concentration.Our findings not only clarify the critical role of molecular engineering in CTC-based TE materials but also provide valuable guidance for developing high-efficiency organic TE materials with versatile practical applications.展开更多
While biomaterials are endowed with sophisticated functions by the temporal dynamics and autonomy derived from non-equilibrium assemblies in biological systems,fabricating advanced materials counterparts with these fe...While biomaterials are endowed with sophisticated functions by the temporal dynamics and autonomy derived from non-equilibrium assemblies in biological systems,fabricating advanced materials counterparts with these features through kinetic control remains rare.Herein,we report a non-equilibrium hydrogel that exhibits autonomous time-dependent ultrabright fluorescence(quantum yield 0.90),achieved through the kinetically controlled incorporation of thermodynamic equilibrium host-vip complexes into a poly(2-hydroxyethyl methacrylate)(PHEMA)network.Transient complexes are programmed by coupling rapid assembly kinetics with the slow competitive binding of the polymer matrix.This kinetic mismatch converts a thermodynamic equilibrium supramolecular system into a non-equilibrium state,generating temporally dynamic fluorescence that cyclically shifts from yellow to green and self-reverts.The programmed temporal dynamics endow the hydrogel with high potential for information encryption applications.展开更多
Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(...Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid),phen(1,10-phenanthroline),bpb(1,4-bis(pyrid-4-yl)benzene),bpa(bis(4-pyridyl)amine),and copper,nickel and cadmium chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and singlecrystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three complexes crystallize in the monoclinic P21/n,tetragonal I42d,and orthorhombic P21212 space groups.The complexes exhibit molecular dimers(1)or 2D metal-organic networks(2 and 3).The catalytic performances in the Knoevenagel reaction of these complexes were investigated.Complex 1 exhibits an effective catalytic activity and excellent reusability as a heterogeneous catalyst in the Knoevenagel reaction at room temperature.CCDC:2463800,1;2463801,2;2463802,3.展开更多
This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the correspo...This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the corresponding ester[Fe_(2)(CO)_(6)(μ‑tedt)](2),where tedt=SCH_(2)CH(CH_(2)OOC(5‑C_(3)HNSCH_(3)))S.Further reactions of complex 2 with tri(ptolyl)phosphine(tp)or tris(4‑fluorophenyl)phosphine(fp)gave the phosphine‑substituted derivatives[Fe_(2)(CO)_(5)(tp)(μ‑tedt)](3)and[Fe_(2)(CO)_(5)(fp)(μ‑tedt)](4).The structures of the newly prepared complexes were elucidated by elemental analysis,NMR,IR,and X‑ray photoelectron spectroscopy.Moreover,single‑crystal X‑ray diffraction analysis confirmed their molecular structures,showing that they contain a di‑iron core ligated by a bridged dithiolate bearing a thiazole moiety and terminal carbonyls.The electrochemical and electrocatalytic proton reduction were probed by cyclic voltammetry,revealing that three complexes can catalyze the reduction of protons to H_(2) under the electrochemical conditions.For comparison,complex 4 possessed the best efficiency with a turnover frequency of 23.5 s^(-1)at 10 mmol·L^(-1)HOAc concentration.In addition,the fungicidal activity of these complexes was also investigated in this study.CCDC:2477511,2;2477512,3;2477513,4.展开更多
A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescenc...A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescence(TADF)properties.All calculations were performed using density functional theory(DFT)and time‑dependent density functional theory(TDDFT).Calculations for electronic structures,frontier molecular orbital characteristics(which determine the efficiency roll‑off effect of the complexes),and photophysical properties were conducted using the Gaussian 09 software package.The calculation of spin‑orbit coupling matrix elements<T|HSOC|S>,which determine the TADF properties of the complexes,was performed using the ORCA software package.The calculation results show that the auxiliary ligand tetraphenylimidodiphosphinate(tpip),a strong electron‑withdrawing group,can mitigate the efficiency roll‑off effect of the complex.Furthermore,TADF is observed in one of the designed complexes,(F_(3)Phppy)_(2)Ir(tpip),where F_(3)Phppy=2‑[4‑(2,4,6‑trifluorophenyl)phenyl]pyridine.展开更多
Enhancing the catalytic activity of catalysts is a core objective in their design and synthesis processes,and the accessibility of active sites is one of the crucial factors determining catalyst activity.Polyoxometala...Enhancing the catalytic activity of catalysts is a core objective in their design and synthesis processes,and the accessibility of active sites is one of the crucial factors determining catalyst activity.Polyoxometalate-based metal-organic complexes(POMOCs)with well-defined structures,which combine the advantages of POMs and MOCs,may offer the possibility to construct catalysts with highly accessible active sites.In this study,a series of POMOCs were successfully designed and synthesized using different POM templates,including[CoII1.5(L)1.5(PMo12O40)(H_(2)O)4]·3H_(2)O(Co-PMo12),[CoII1.5(L)1.5(PW12O40)(H_(2)O)4]·3H_(2)O(Co-PW12),[CoII2(L)2-(SiW12O40)(H_(2)O)4]·11H_(2)O(Co-SiW12),and H[CoII2.5(L)3-(P2W18O62)(H_(2)O)8]·10H_(2)O(Co-P2W18),which were characterized by Fourier transform infrared spectroscopy,powder X-ray diffraction,and single crystal X-ray diffraction.The differences in catalytic activity among the four POMOCs for olefin epoxidation were attributed to the distinct accessibility of Co(II)sites upon thermal activation.Among them,Co-P2W18 achieved a remarkable 99%yield of 1,2-epoxycyclooctane within 3 h at room temperature using O_(2)as the oxidant,owing to its highly accessible unsaturated Co(II)sites.Co-P2W18 exhibits significantly superior catalytic activity for the cyclooctene epoxidation reaction compared to most reported catalysts.Additionally,the reaction mechanism was investigated using density functional theory.展开更多
The dominant oxidation state for lanthanide ions is+3 due to the loss of 5d and 6s electrons from their shared configuration of[Xe]4f^(0-14)5d^(0-16)s(2).There are however several exceptions because of the completely ...The dominant oxidation state for lanthanide ions is+3 due to the loss of 5d and 6s electrons from their shared configuration of[Xe]4f^(0-14)5d^(0-16)s(2).There are however several exceptions because of the completely empty(Ce(Ⅳ)),half-filled(Eu(Ⅱ)),or fully filled(Yb(Ⅱ))4f subshell.As such,stable complexes are formed primarily with Ln(Ⅲ)ions[1].展开更多
Intracellular bacteria(ICB),cloaked by the protective barriers of host cells,pose a formidable challenge to selective and efficient eradication.The employment of activatable photosensitizers based antibacterial photod...Intracellular bacteria(ICB),cloaked by the protective barriers of host cells,pose a formidable challenge to selective and efficient eradication.The employment of activatable photosensitizers based antibacterial photodynamic therapy(a PDT)holds significant potential for selective imaging and photo-inactivation of ICB while minimizing side effects on normal cells.Drawing inspiration from the elevated hypochlorous acid(HClO)levels in ICB infected phagocytes,herein we firstly designed and synthesized a series of HCl Oresponsive dinuclear Ru(Ⅱ)complexes(Ru1-Ru3)to achieve such a goal.Initially,the luminescence,^(1)O_(2)generation and a PDT activity of these Ru(Ⅱ)complexes were suppressed due to the quenching effect of the azo group,but were recovered after reaction with HCl O in solutions or within ICB infected phagocytes.The detailed results revealed that Ru1 and Ru3 could not only selectively visualize ICB,but also demonstrated remarkable a PDT activity against ICB,surpassing vancomycin both in vitro and in vivo.展开更多
The reaction behaviors of the title complexes have been studied in thesystem of dinitrogen gas by means of in situ IR. It has been found that some activefragments created at some stage of the thermal decomposition pro...The reaction behaviors of the title complexes have been studied in thesystem of dinitrogen gas by means of in situ IR. It has been found that some activefragments created at some stage of the thermal decomposition process of the complexes.enable.the acetic acid both obtained from the ligand of the complexes and introducedfrom outside to convert to acetone by decarboxylation. Their optimum reaction temperatures are of 240~270℃ for [Fe2MnO(O2CCH3),(H2O)3], 290~320 C for [Fe3Q(O2CCH3)6(H2O)3], 300~330℃ for [Fe2CoO(O2CCH3),(H2O)3] and 320~ 350℃for [Fe2NiO(O2CCH3)6(H2O)3], indicating the lowering sequence of the activity of active species. At the same time it has been shown that this activity may come from thejoined contributions of both the coordinating capability of the hetero-metals in the complexes and their structural factors. On the basis of the TGA, DTA and EI-MS data,the composition of the active fragments has been tentatively inferred as [Fe2MnO(O2CCH3)3-2].展开更多
Two novel lanthanide complexes,[Sm_(2)(BA)_(6)(4-OH-terpy)_(2)]·2H_(2)O·2EtOH(1)and[Pr_(2)(BA)_(6)(4-OH-terpy)_(2)(H_(2)O)_(2)]·HBA·H_(2)O(2),where HBA=benzoic acid,4-OH-terpy=4-hydroxy-2,2'∶6...Two novel lanthanide complexes,[Sm_(2)(BA)_(6)(4-OH-terpy)_(2)]·2H_(2)O·2EtOH(1)and[Pr_(2)(BA)_(6)(4-OH-terpy)_(2)(H_(2)O)_(2)]·HBA·H_(2)O(2),where HBA=benzoic acid,4-OH-terpy=4-hydroxy-2,2'∶6',2″-terpyridine,were successfully synthesized using ultrasonic dissolution and the conventional solution method with two mixed ligands HBA and 4-OH-terpy.During the synthesis,4-OH-terpy was involved in the reaction as a neutral ligand,while HBA,in its deprotonated form(BA-),coordinated with the lanthanide ions as an acidic ligand.The crystal structures of these two complexes were precisely determined by single-crystal X-ray diffraction.Elemental analysis,infrared and Raman spectroscopy,and powder X-ray diffraction techniques were also employed to further explore the physicochemical properties of the two complexes.The single-crystal X-ray diffraction data indicate that,despite their structural differences,both complexes belong to the triclinic crystal system P1 space group.The central lanthanide ions have the same coordination number but exhibit different coordination environments.To comprehensively evaluate the thermal stability of these two complexes,comprehensive tests including thermogravimetric analysis,differential thermogravimetric analysis,differential scanning calorimetry,Fourier transform infrared spectroscopy,and mass spectrometry were conducted.Meanwhile,an in-depth investigation was conducted into the 3D infrared stacked images and mass spectra of the gases emitted from the complexes.In addition,studies of the fluorescence properties of complex1 showed that it exhibited fluorescence emission matching the Sm^(3+)characteristic transition.展开更多
To extend a new family of aminophosphine-coordinated[FeFe]-hydrogenase mimics for catalytic hydro-gen(H_(2))evolution,we carried out the ligand substitutions of diiron hexacarbonyl precursors[Fe_(2)(μ-X_(2)pdt)(CO)_(...To extend a new family of aminophosphine-coordinated[FeFe]-hydrogenase mimics for catalytic hydro-gen(H_(2))evolution,we carried out the ligand substitutions of diiron hexacarbonyl precursors[Fe_(2)(μ-X_(2)pdt)(CO)_(6)](X_(2)pdt=(SCH_(2))_(2)CX_(2),X=Me,H)with aminodiphosphines(Ph_(2)PCH_(2))_(2)NY(Y=(CH_(2))_(2)OH,(CH_(2))_(3)OH)to obtain two new diiron aminophosphine complexes[Fe_(2)(L1)(μ-Me_(2)pdt)(CO)_(5)](1)and[Fe_(2)(L2)(μ-H_(2)pdt)(CO)_(5)](2),where L1=3-[(diphe-nylphosphaneyl)methyl]oxazolidine,L2=3-[(diphenylphosphaneyl)methyl]-1,3-oxazinane.Moreover,the structures of 1 and 2 have been fully confirmed by elemental analysis,spectroscopic techniques,and single-crystal X-ray diffraction.Using cyclic voltammetry(CV),we investigated the electrochemical redox performance and proton reduc-tion activities of 1 and 2 in acetic acid(HOAc).The CV study indicates that diiron aminophosphine complexes 1 and 2 can be considered to be hydrogenase-inspired diiron molecular electrocatalysts for the reduction of protons into H 2 generation in the presence of HOAc.CCDC:2443967,1;2443969,2.展开更多
We have examined the theoretical implications of combining two main and three auxiliary ligands to form several Ir(Ⅲ)complexes featuring a transition metal as their core atom to identify some appropriate organic ligh...We have examined the theoretical implications of combining two main and three auxiliary ligands to form several Ir(Ⅲ)complexes featuring a transition metal as their core atom to identify some appropriate organic lightemitting diode(OLED)materials.By utilizing electronic structure,frontier molecular orbitals,minimum single-line absorption,triplet excited states,and emission spectral data derived from the density functional theory,the usefulness of these Ir(Ⅲ)complexes,including(piq)_(2)Ir(acac),(piq)_(2)Ir(tmd),(piq)_(2)Ir(tpip),(fpiq)_(2)Ir(acac),(fpiq)_(2)Ir(tmd),and(fpiq)_(2)Ir(tpip),in OLEDs was examined,where piq=1-phenylisoquinoline,fpiq=1-(4-fluorophenyl)isoquinoline,acac=(3Z)-4-hydroxypent-3-en-2-one,tmd=(4Z)-5-hydroxy-2,2,6,6-tetramethylhept-4-en-3-one,and tpip=tetraphenylimido-diphosphonate.These complexes all have low-efficiency roll-off properties,especially(fpiq)_(2)Ir(tpip).Some researchers have successfully synthesized complexes extremely similar to(piq)_(2)Ir(acac)through the Suzuki-Miyaura coupling reaction.展开更多
Three efficient methods for the synthesis of a series of Cu(Ⅱ) and Cu(Ⅰ) complexes based on imidazo[1,5-a]pyridine derivatives were developed.These methods include the following:(ⅰ)Cu(Ⅱ) salts were used as metal s...Three efficient methods for the synthesis of a series of Cu(Ⅱ) and Cu(Ⅰ) complexes based on imidazo[1,5-a]pyridine derivatives were developed.These methods include the following:(ⅰ)Cu(Ⅱ) salts were used as metal sources and N,N-dimethylformamide was employed as a solvent as well as a reductant to produce Cu(Ⅰ) complexes.(ⅱ) An iodide-containing compound was utilized as a ligand and iodide source to prepare complexes.An in situ metalligand reaction occurred and an iodide-bridged copper complex was generated.(ⅲ) A series of aldehydes were added to the reaction systems to induce in situ metal-ligand reactions between the aldehydes and the imidazo[1,5-a]pyridine derivatives,producing polydentate ligand scaffolds.Eight complexes were prepared and characterized.The catalytic activities of these complexes toward the ketalization of ketones by ethylene glycol were investigated.With the exception of complex4,the remaining seven complexes all showed high catalytic activity.The lower activity of 4 may be due to the larger radius of bridging iodide ions and the shorter Cu(Ⅰ)…Cu(Ⅰ) distance.CCDC:2357696,1·2CH_(2)Cl_(2);2357697,2;2018292,3;2092192,4;2092190,5;2155557,6;2406155,7;2406156,8·EtOH.展开更多
Transition metal possesses a unique d-orbital electronic structure,which imparts a diverse range of physical and chemical properties.These properties render them significant in fields such as chemistry and materials s...Transition metal possesses a unique d-orbital electronic structure,which imparts a diverse range of physical and chemical properties.These properties render them significant in fields such as chemistry and materials science.The distinctive optical,electrical,and magnetic properties of these complexes can be attributed to the variations in the quantity of d-orbital electrons,thereby influencing their spin and orbital characteristics.The d-orbitals facilitate the formation of stable multidirectional bonds with ligands,resulting in a variety of geometric structures and rich coordination chemistry.These interactions result in variations in energy levels,thereby producing diverse electrical properties,including low attenuation coefficients,high rectification ratios,and unique multichannel transmission.Moreover,the unpaired electrons inthe d-orbitals can give rise to diverse magnetic behaviors,leading to magnetic effects such as spin-related interfaces,switches,and magnetoresistance.This paves the way for extensive possibilities in the design and application of single-molecule devices.This review elaborates on singlemolecule physical properties of transition metal complexes,including length attenuation,rectification,multi-channel transmission,thermoelectric effect,and spin regulation,which are vital for the functionalization and regulation of molecular electronics.In addition,this review also explores the correlation between these physical properties and the electronic structure of transition metals,discussing the broad prospects of transition metal complexes in the fields of nanoelectronics,optoelectronics,and quantum technology.展开更多
In this work,we synthesize two luminescent Pt(Ⅱ)complexes using differentπ-conjugated bidentate ligands.Both complexes are assembled into three-dimensional(3D)networks through non-classical intermolecular interactio...In this work,we synthesize two luminescent Pt(Ⅱ)complexes using differentπ-conjugated bidentate ligands.Both complexes are assembled into three-dimensional(3D)networks through non-classical intermolecular interactions in the crystal state.Unexpectedly,substituting pyridine with the more extensivelyπ-conjugated quinoline significantly increases the dihedral angles between the phenyl and quinolyl groups of the bidentate ligands.This alteration disrupts theπ-πinteractions between molecules,resulting in distinct optical properties upon exposure to external stimuli.By integrating these complexes into polymers,we fabricate electrospun films containing luminescent nanofibers that exhibit reversible optical changes.These findings have paved the way for the development of high-performance optical encryption and anti-counterfeiting materials,achieved through the employment of simple chromophores.展开更多
Photochromic materials attract significant attention for their applications in anticounterfeiting devices,optical switches and molecular sensors.However,the influence of solvent molecules,particularly coordinated solv...Photochromic materials attract significant attention for their applications in anticounterfeiting devices,optical switches and molecular sensors.However,the influence of solvent molecules,particularly coordinated solvents,on electron transfer(ET)photochromic systems remains poorly understood.In this study,we synthesized a series of isostructural metal-organic complexes(MOCs),[Mn(ADC)(L)]n(ADC=9,10-anthracenedicarboxylic acid,L=DMF for 1,DMA for 2,MEA for 3,and DMSO for 4)to investigate the solvent-chromic behavior.All these MOCs exhibit typical radical-induced chromism upon illumination with a xenon lamp at room temperature.It is worth noting that coordination solvent molecules significantly modulate the photochromic response rate.Among the compounds studied,compound 1 exhibits the fastest response,while compound 3 shows the slowest.This variation in rate correlates with differences in the optimal ET path length within their structures.Specifically,solvent molecules regulate the C-H…π interaction distance through their steric hindrance and electronic prop-erties.Shorter C-H…π paths facilitate more efficient ET upon photoexcitation,thus leading to faster photo-chromic response rates.Furthermore,illumination actuates magnetic couplings between photogenerated radicals and Mn^(2+)centers,resulting in a significant increase in room-temperature magnetization,demonstrating a photomagnetic response.This study demonstrates that coordinating solvent selection effectively controls photoinduced ET behavior,providing new insights for designing advanced photoactive materials.展开更多
Microstructure topology evolution during severe plastic deformation(SPD)is crucial for understanding and optimising the mechanical properties of metallic materials,though its prediction remains challenging.Herein,we c...Microstructure topology evolution during severe plastic deformation(SPD)is crucial for understanding and optimising the mechanical properties of metallic materials,though its prediction remains challenging.Herein,we combine discrete cell complexes(DCC),a fully discrete algebraic topology model-with finite element analysis(FEA)to simulate and analyse the microstructure topology of pure copper under SPD.Using DCC,we model the evolution of microstructure topology characterised by Betti numbers(β_(0),β_(1),β_(2))and Euler characteristic(χ).This captures key changes in GBNs and topological features within representative volume elements(RVEs)containing several hundred grains during SPD-induced recrystallisation.As SPD cycles increase,high-angle grain boundaries(HAGBs)progressively form.Topological analysis reveals an overall decrease in β_(0)values,indicating fewer isolated HAGB substructures,while β_(2) values show a steady upward trend,highlighting new grain formation.Leveraging DCC-derived RVE topology and FEA-generated plastic strain data,we directly simulate the evolution and spatial distribution of microstructure topology and HAGB fraction in a copper tube undergoing cyclic parallel tube channel angular pressing(PTCAP),a representative SPD technique.Within the tube,the HAGB fraction continuously increases with PTCAP cycles,reflecting the microstructure’s gradual transition from subgrains to fully-formed grains.Analysis of Betti number distribution and evolution reveals the microstructural reconstruction mechanism underpinning this subgrain to grain transition during PTCAP.We further demonstrate the significant influence of spatially non-uniform plastic strain distribution on microstructure reconstruction kinetics.This study demonstrates a feasible approach for simulating microstructure topology evolution of metals processed by cyclic SPD via the integration of DCC and FEA.展开更多
文摘Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been constructed hydrothermally at 160℃ using H_(3)tpta([1,1':3',1″-terphenyl]-4,4',5'-tricarboxylic acid),py(pyridine),H_(2)biim(2,2'-biimidazole),dpe(1,2-di(4-pyridyl)ethylene),and zinc,nickel and cadmium chlorides,resulting in the formation of stable crystalline solids which were subsequently analyzed using infrared spectroscopy,element analysis,thermogravimetric analysis,as well as structural analyses conducted via single-crystal X-ray diffraction.The findings from these single-crystal Xray diffraction studies indicate that complexes 1-3 form crystals within the monoclinic system P2_(1)/c space group(1)or triclinic system P1 space group(2 and 3),and possess 1D,0D,and 3D structures,respectively.Complex 1 demonstrated substantial catalytic efficiency and excellent reusability as a heterogeneous catalyst in the reaction of Knoevenagel condensation under ambient temperature conditions.In addition,complex 1 also showcased notable anti-wear performance when used in polyalphaolefin synthetic lubricants.CCDC:2449810,1;2449811,2;2449812,3.
文摘Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6.
文摘The complexes 1-4 of cyclobutanocucurbit[5]uril(CyB5Q[5])with Na^(+)/K^(+)have been synthesized and characterized by single-crystal X-ray diffraction.The results show that although the inorganic salts are used when the cations are the same and the anions are different,in complex 1,Na^(+)closes one port of CyB5Q[5]through Na—O seven coordination bonds to form a molecular bowl;in complex 3,Na^(+)completely closes the two ports of CyB5Q[5]to form a molecular capsule with six Na—O coordination bonds;in complexes 2 and 4,the two ports of CyB5Q[5]are completely closed to form K—O coordinated molecular capsules,but the K^(+)of complex 2 is six-coordinated and that of complex 4 is eight-/nine-coordinated.and complex 4 are connected by three oxygen bridges to form a 1D molecular chain.CCDC:2457122,1;2457121,2;2457400,3;2457120,4.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Science(No.XDB0520000)the National Natural Science Foundation of China(Nos.52273170 and 52394271)the National Key R&D Program of China(No.2022YFA1203200).
文摘Charge-transfer complexes(CTCs)have emerged as promising n-type organic thermoelectric(TE)materials due to their inherent high electrical conductivity and tunable transport polarities.In this study,we performed a comprehensive first-principles investigation on the TE properties of nine CTCs comprised of 2,7-dialkyl[1]benzothieno[3,2-b][1]benzothiophenes(CnBTBT,n=4,8,12)as donors and fluorinated derivatives of tetracyanoquinodimethane(F_(m)TCNQ,m=0,2,4)as acceptors,aiming to identify high-performance n-type organic TE materials and elucidate the underlying structure-property relationships.Our calculation results,based on the Boltzmann transport equation and deformation potential theory,reveal that the length of the alkyl side chains and the number of fluorine substitutions significantly impact their electronic structures and TE properties.Notably,the CnBTBT-F_(m)TCNQ CTCs with shorter alkyl chains and more fluorine substitution demonstrate superior n-type characteristics,particularly C4BTBT-F4TCNQ,which achieves an excellent power factor of 671µW cm^(-1) K^(-2) at an optimal charge carrier concentration.Our findings not only clarify the critical role of molecular engineering in CTC-based TE materials but also provide valuable guidance for developing high-efficiency organic TE materials with versatile practical applications.
基金supported by the National Natural Science Foundation of China(22025503,22220102004,22401093)the Science and Technology Commission of Shanghai Municipality(24DX1400200)+2 种基金the Innovation Program of Shanghai Municipal Education Commission(2023ZKZD40)the Programme of Introducing Talents of Discipline to Universities(B16017)the China Postdoctoral Science Foundation(2023M741167,GZB20230211,2024T170273)。
文摘While biomaterials are endowed with sophisticated functions by the temporal dynamics and autonomy derived from non-equilibrium assemblies in biological systems,fabricating advanced materials counterparts with these features through kinetic control remains rare.Herein,we report a non-equilibrium hydrogel that exhibits autonomous time-dependent ultrabright fluorescence(quantum yield 0.90),achieved through the kinetically controlled incorporation of thermodynamic equilibrium host-vip complexes into a poly(2-hydroxyethyl methacrylate)(PHEMA)network.Transient complexes are programmed by coupling rapid assembly kinetics with the slow competitive binding of the polymer matrix.This kinetic mismatch converts a thermodynamic equilibrium supramolecular system into a non-equilibrium state,generating temporally dynamic fluorescence that cyclically shifts from yellow to green and self-reverts.The programmed temporal dynamics endow the hydrogel with high potential for information encryption applications.
文摘Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid),phen(1,10-phenanthroline),bpb(1,4-bis(pyrid-4-yl)benzene),bpa(bis(4-pyridyl)amine),and copper,nickel and cadmium chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and singlecrystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three complexes crystallize in the monoclinic P21/n,tetragonal I42d,and orthorhombic P21212 space groups.The complexes exhibit molecular dimers(1)or 2D metal-organic networks(2 and 3).The catalytic performances in the Knoevenagel reaction of these complexes were investigated.Complex 1 exhibits an effective catalytic activity and excellent reusability as a heterogeneous catalyst in the Knoevenagel reaction at room temperature.CCDC:2463800,1;2463801,2;2463802,3.
文摘This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the corresponding ester[Fe_(2)(CO)_(6)(μ‑tedt)](2),where tedt=SCH_(2)CH(CH_(2)OOC(5‑C_(3)HNSCH_(3)))S.Further reactions of complex 2 with tri(ptolyl)phosphine(tp)or tris(4‑fluorophenyl)phosphine(fp)gave the phosphine‑substituted derivatives[Fe_(2)(CO)_(5)(tp)(μ‑tedt)](3)and[Fe_(2)(CO)_(5)(fp)(μ‑tedt)](4).The structures of the newly prepared complexes were elucidated by elemental analysis,NMR,IR,and X‑ray photoelectron spectroscopy.Moreover,single‑crystal X‑ray diffraction analysis confirmed their molecular structures,showing that they contain a di‑iron core ligated by a bridged dithiolate bearing a thiazole moiety and terminal carbonyls.The electrochemical and electrocatalytic proton reduction were probed by cyclic voltammetry,revealing that three complexes can catalyze the reduction of protons to H_(2) under the electrochemical conditions.For comparison,complex 4 possessed the best efficiency with a turnover frequency of 23.5 s^(-1)at 10 mmol·L^(-1)HOAc concentration.In addition,the fungicidal activity of these complexes was also investigated in this study.CCDC:2477511,2;2477512,3;2477513,4.
文摘A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescence(TADF)properties.All calculations were performed using density functional theory(DFT)and time‑dependent density functional theory(TDDFT).Calculations for electronic structures,frontier molecular orbital characteristics(which determine the efficiency roll‑off effect of the complexes),and photophysical properties were conducted using the Gaussian 09 software package.The calculation of spin‑orbit coupling matrix elements<T|HSOC|S>,which determine the TADF properties of the complexes,was performed using the ORCA software package.The calculation results show that the auxiliary ligand tetraphenylimidodiphosphinate(tpip),a strong electron‑withdrawing group,can mitigate the efficiency roll‑off effect of the complex.Furthermore,TADF is observed in one of the designed complexes,(F_(3)Phppy)_(2)Ir(tpip),where F_(3)Phppy=2‑[4‑(2,4,6‑trifluorophenyl)phenyl]pyridine.
基金financially supported by the National Natural Science Foundation of China(22271021,21971024,and 22201021)the Natural Science Foundation and Education Department of Liaoning Province(LJ232410167011)。
文摘Enhancing the catalytic activity of catalysts is a core objective in their design and synthesis processes,and the accessibility of active sites is one of the crucial factors determining catalyst activity.Polyoxometalate-based metal-organic complexes(POMOCs)with well-defined structures,which combine the advantages of POMs and MOCs,may offer the possibility to construct catalysts with highly accessible active sites.In this study,a series of POMOCs were successfully designed and synthesized using different POM templates,including[CoII1.5(L)1.5(PMo12O40)(H_(2)O)4]·3H_(2)O(Co-PMo12),[CoII1.5(L)1.5(PW12O40)(H_(2)O)4]·3H_(2)O(Co-PW12),[CoII2(L)2-(SiW12O40)(H_(2)O)4]·11H_(2)O(Co-SiW12),and H[CoII2.5(L)3-(P2W18O62)(H_(2)O)8]·10H_(2)O(Co-P2W18),which were characterized by Fourier transform infrared spectroscopy,powder X-ray diffraction,and single crystal X-ray diffraction.The differences in catalytic activity among the four POMOCs for olefin epoxidation were attributed to the distinct accessibility of Co(II)sites upon thermal activation.Among them,Co-P2W18 achieved a remarkable 99%yield of 1,2-epoxycyclooctane within 3 h at room temperature using O_(2)as the oxidant,owing to its highly accessible unsaturated Co(II)sites.Co-P2W18 exhibits significantly superior catalytic activity for the cyclooctene epoxidation reaction compared to most reported catalysts.Additionally,the reaction mechanism was investigated using density functional theory.
基金supported by the National Natural Science Foundation of China(22101116,92261203,21971106)Shenzhen Fundamental Research Program(JCYJ20220530115001002 and JCYJ20220818100417037).
文摘The dominant oxidation state for lanthanide ions is+3 due to the loss of 5d and 6s electrons from their shared configuration of[Xe]4f^(0-14)5d^(0-16)s(2).There are however several exceptions because of the completely empty(Ce(Ⅳ)),half-filled(Eu(Ⅱ)),or fully filled(Yb(Ⅱ))4f subshell.As such,stable complexes are formed primarily with Ln(Ⅲ)ions[1].
基金supported by National Natural Science Foundation of China(No.22371289)。
文摘Intracellular bacteria(ICB),cloaked by the protective barriers of host cells,pose a formidable challenge to selective and efficient eradication.The employment of activatable photosensitizers based antibacterial photodynamic therapy(a PDT)holds significant potential for selective imaging and photo-inactivation of ICB while minimizing side effects on normal cells.Drawing inspiration from the elevated hypochlorous acid(HClO)levels in ICB infected phagocytes,herein we firstly designed and synthesized a series of HCl Oresponsive dinuclear Ru(Ⅱ)complexes(Ru1-Ru3)to achieve such a goal.Initially,the luminescence,^(1)O_(2)generation and a PDT activity of these Ru(Ⅱ)complexes were suppressed due to the quenching effect of the azo group,but were recovered after reaction with HCl O in solutions or within ICB infected phagocytes.The detailed results revealed that Ru1 and Ru3 could not only selectively visualize ICB,but also demonstrated remarkable a PDT activity against ICB,surpassing vancomycin both in vitro and in vivo.
文摘The reaction behaviors of the title complexes have been studied in thesystem of dinitrogen gas by means of in situ IR. It has been found that some activefragments created at some stage of the thermal decomposition process of the complexes.enable.the acetic acid both obtained from the ligand of the complexes and introducedfrom outside to convert to acetone by decarboxylation. Their optimum reaction temperatures are of 240~270℃ for [Fe2MnO(O2CCH3),(H2O)3], 290~320 C for [Fe3Q(O2CCH3)6(H2O)3], 300~330℃ for [Fe2CoO(O2CCH3),(H2O)3] and 320~ 350℃for [Fe2NiO(O2CCH3)6(H2O)3], indicating the lowering sequence of the activity of active species. At the same time it has been shown that this activity may come from thejoined contributions of both the coordinating capability of the hetero-metals in the complexes and their structural factors. On the basis of the TGA, DTA and EI-MS data,the composition of the active fragments has been tentatively inferred as [Fe2MnO(O2CCH3)3-2].
文摘Two novel lanthanide complexes,[Sm_(2)(BA)_(6)(4-OH-terpy)_(2)]·2H_(2)O·2EtOH(1)and[Pr_(2)(BA)_(6)(4-OH-terpy)_(2)(H_(2)O)_(2)]·HBA·H_(2)O(2),where HBA=benzoic acid,4-OH-terpy=4-hydroxy-2,2'∶6',2″-terpyridine,were successfully synthesized using ultrasonic dissolution and the conventional solution method with two mixed ligands HBA and 4-OH-terpy.During the synthesis,4-OH-terpy was involved in the reaction as a neutral ligand,while HBA,in its deprotonated form(BA-),coordinated with the lanthanide ions as an acidic ligand.The crystal structures of these two complexes were precisely determined by single-crystal X-ray diffraction.Elemental analysis,infrared and Raman spectroscopy,and powder X-ray diffraction techniques were also employed to further explore the physicochemical properties of the two complexes.The single-crystal X-ray diffraction data indicate that,despite their structural differences,both complexes belong to the triclinic crystal system P1 space group.The central lanthanide ions have the same coordination number but exhibit different coordination environments.To comprehensively evaluate the thermal stability of these two complexes,comprehensive tests including thermogravimetric analysis,differential thermogravimetric analysis,differential scanning calorimetry,Fourier transform infrared spectroscopy,and mass spectrometry were conducted.Meanwhile,an in-depth investigation was conducted into the 3D infrared stacked images and mass spectra of the gases emitted from the complexes.In addition,studies of the fluorescence properties of complex1 showed that it exhibited fluorescence emission matching the Sm^(3+)characteristic transition.
文摘To extend a new family of aminophosphine-coordinated[FeFe]-hydrogenase mimics for catalytic hydro-gen(H_(2))evolution,we carried out the ligand substitutions of diiron hexacarbonyl precursors[Fe_(2)(μ-X_(2)pdt)(CO)_(6)](X_(2)pdt=(SCH_(2))_(2)CX_(2),X=Me,H)with aminodiphosphines(Ph_(2)PCH_(2))_(2)NY(Y=(CH_(2))_(2)OH,(CH_(2))_(3)OH)to obtain two new diiron aminophosphine complexes[Fe_(2)(L1)(μ-Me_(2)pdt)(CO)_(5)](1)and[Fe_(2)(L2)(μ-H_(2)pdt)(CO)_(5)](2),where L1=3-[(diphe-nylphosphaneyl)methyl]oxazolidine,L2=3-[(diphenylphosphaneyl)methyl]-1,3-oxazinane.Moreover,the structures of 1 and 2 have been fully confirmed by elemental analysis,spectroscopic techniques,and single-crystal X-ray diffraction.Using cyclic voltammetry(CV),we investigated the electrochemical redox performance and proton reduc-tion activities of 1 and 2 in acetic acid(HOAc).The CV study indicates that diiron aminophosphine complexes 1 and 2 can be considered to be hydrogenase-inspired diiron molecular electrocatalysts for the reduction of protons into H 2 generation in the presence of HOAc.CCDC:2443967,1;2443969,2.
文摘We have examined the theoretical implications of combining two main and three auxiliary ligands to form several Ir(Ⅲ)complexes featuring a transition metal as their core atom to identify some appropriate organic lightemitting diode(OLED)materials.By utilizing electronic structure,frontier molecular orbitals,minimum single-line absorption,triplet excited states,and emission spectral data derived from the density functional theory,the usefulness of these Ir(Ⅲ)complexes,including(piq)_(2)Ir(acac),(piq)_(2)Ir(tmd),(piq)_(2)Ir(tpip),(fpiq)_(2)Ir(acac),(fpiq)_(2)Ir(tmd),and(fpiq)_(2)Ir(tpip),in OLEDs was examined,where piq=1-phenylisoquinoline,fpiq=1-(4-fluorophenyl)isoquinoline,acac=(3Z)-4-hydroxypent-3-en-2-one,tmd=(4Z)-5-hydroxy-2,2,6,6-tetramethylhept-4-en-3-one,and tpip=tetraphenylimido-diphosphonate.These complexes all have low-efficiency roll-off properties,especially(fpiq)_(2)Ir(tpip).Some researchers have successfully synthesized complexes extremely similar to(piq)_(2)Ir(acac)through the Suzuki-Miyaura coupling reaction.
文摘Three efficient methods for the synthesis of a series of Cu(Ⅱ) and Cu(Ⅰ) complexes based on imidazo[1,5-a]pyridine derivatives were developed.These methods include the following:(ⅰ)Cu(Ⅱ) salts were used as metal sources and N,N-dimethylformamide was employed as a solvent as well as a reductant to produce Cu(Ⅰ) complexes.(ⅱ) An iodide-containing compound was utilized as a ligand and iodide source to prepare complexes.An in situ metalligand reaction occurred and an iodide-bridged copper complex was generated.(ⅲ) A series of aldehydes were added to the reaction systems to induce in situ metal-ligand reactions between the aldehydes and the imidazo[1,5-a]pyridine derivatives,producing polydentate ligand scaffolds.Eight complexes were prepared and characterized.The catalytic activities of these complexes toward the ketalization of ketones by ethylene glycol were investigated.With the exception of complex4,the remaining seven complexes all showed high catalytic activity.The lower activity of 4 may be due to the larger radius of bridging iodide ions and the shorter Cu(Ⅰ)…Cu(Ⅰ) distance.CCDC:2357696,1·2CH_(2)Cl_(2);2357697,2;2018292,3;2092192,4;2092190,5;2155557,6;2406155,7;2406156,8·EtOH.
基金financially supported by the National Key R&D Program of China(Nos.2021YFA1200102,2021YFA1200101,2023YFF1205803,2022YFE0128700)the National Natural Science Foundation of China(Nos.22173050,22150013,21727806,21933001)+1 种基金Beijing National Laboratory for Molecular Sciences(No.BNLMS-CXXM-202407)the Natural Science Foundation of Beijing(No.2222009)
文摘Transition metal possesses a unique d-orbital electronic structure,which imparts a diverse range of physical and chemical properties.These properties render them significant in fields such as chemistry and materials science.The distinctive optical,electrical,and magnetic properties of these complexes can be attributed to the variations in the quantity of d-orbital electrons,thereby influencing their spin and orbital characteristics.The d-orbitals facilitate the formation of stable multidirectional bonds with ligands,resulting in a variety of geometric structures and rich coordination chemistry.These interactions result in variations in energy levels,thereby producing diverse electrical properties,including low attenuation coefficients,high rectification ratios,and unique multichannel transmission.Moreover,the unpaired electrons inthe d-orbitals can give rise to diverse magnetic behaviors,leading to magnetic effects such as spin-related interfaces,switches,and magnetoresistance.This paves the way for extensive possibilities in the design and application of single-molecule devices.This review elaborates on singlemolecule physical properties of transition metal complexes,including length attenuation,rectification,multi-channel transmission,thermoelectric effect,and spin regulation,which are vital for the functionalization and regulation of molecular electronics.In addition,this review also explores the correlation between these physical properties and the electronic structure of transition metals,discussing the broad prospects of transition metal complexes in the fields of nanoelectronics,optoelectronics,and quantum technology.
基金supported by the National Natural Science Foundation of China(Nos.22201057 and 22472044)Zhejiang Provincial Natural Science Foundation of China(Nos.LR22B010001 and LQ23B010001)。
文摘In this work,we synthesize two luminescent Pt(Ⅱ)complexes using differentπ-conjugated bidentate ligands.Both complexes are assembled into three-dimensional(3D)networks through non-classical intermolecular interactions in the crystal state.Unexpectedly,substituting pyridine with the more extensivelyπ-conjugated quinoline significantly increases the dihedral angles between the phenyl and quinolyl groups of the bidentate ligands.This alteration disrupts theπ-πinteractions between molecules,resulting in distinct optical properties upon exposure to external stimuli.By integrating these complexes into polymers,we fabricate electrospun films containing luminescent nanofibers that exhibit reversible optical changes.These findings have paved the way for the development of high-performance optical encryption and anti-counterfeiting materials,achieved through the employment of simple chromophores.
基金supported by the National Natural Science Foundation of China(22171155,22571174)Natural Science Foundation of Shandong Province(ZR2022YQ07)+1 种基金Taishan Scholar Program(tsqn202306166)the State Key Laboratory of Fine Chemicals,Dalian University of Technology(KF 2409).
文摘Photochromic materials attract significant attention for their applications in anticounterfeiting devices,optical switches and molecular sensors.However,the influence of solvent molecules,particularly coordinated solvents,on electron transfer(ET)photochromic systems remains poorly understood.In this study,we synthesized a series of isostructural metal-organic complexes(MOCs),[Mn(ADC)(L)]n(ADC=9,10-anthracenedicarboxylic acid,L=DMF for 1,DMA for 2,MEA for 3,and DMSO for 4)to investigate the solvent-chromic behavior.All these MOCs exhibit typical radical-induced chromism upon illumination with a xenon lamp at room temperature.It is worth noting that coordination solvent molecules significantly modulate the photochromic response rate.Among the compounds studied,compound 1 exhibits the fastest response,while compound 3 shows the slowest.This variation in rate correlates with differences in the optimal ET path length within their structures.Specifically,solvent molecules regulate the C-H…π interaction distance through their steric hindrance and electronic prop-erties.Shorter C-H…π paths facilitate more efficient ET upon photoexcitation,thus leading to faster photo-chromic response rates.Furthermore,illumination actuates magnetic couplings between photogenerated radicals and Mn^(2+)centers,resulting in a significant increase in room-temperature magnetization,demonstrating a photomagnetic response.This study demonstrates that coordinating solvent selection effectively controls photoinduced ET behavior,providing new insights for designing advanced photoactive materials.
基金support from Outstanding Youth Fund of Jiangsu Province(BK20240077)Key Project(Provincial-Municipal Joint)of Jiangsu Province(BK20243044)+2 种基金Fundamental Research Funds for the Central Universities(NE2024001)National Youth Talents Programof Chinaa project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Microstructure topology evolution during severe plastic deformation(SPD)is crucial for understanding and optimising the mechanical properties of metallic materials,though its prediction remains challenging.Herein,we combine discrete cell complexes(DCC),a fully discrete algebraic topology model-with finite element analysis(FEA)to simulate and analyse the microstructure topology of pure copper under SPD.Using DCC,we model the evolution of microstructure topology characterised by Betti numbers(β_(0),β_(1),β_(2))and Euler characteristic(χ).This captures key changes in GBNs and topological features within representative volume elements(RVEs)containing several hundred grains during SPD-induced recrystallisation.As SPD cycles increase,high-angle grain boundaries(HAGBs)progressively form.Topological analysis reveals an overall decrease in β_(0)values,indicating fewer isolated HAGB substructures,while β_(2) values show a steady upward trend,highlighting new grain formation.Leveraging DCC-derived RVE topology and FEA-generated plastic strain data,we directly simulate the evolution and spatial distribution of microstructure topology and HAGB fraction in a copper tube undergoing cyclic parallel tube channel angular pressing(PTCAP),a representative SPD technique.Within the tube,the HAGB fraction continuously increases with PTCAP cycles,reflecting the microstructure’s gradual transition from subgrains to fully-formed grains.Analysis of Betti number distribution and evolution reveals the microstructural reconstruction mechanism underpinning this subgrain to grain transition during PTCAP.We further demonstrate the significant influence of spatially non-uniform plastic strain distribution on microstructure reconstruction kinetics.This study demonstrates a feasible approach for simulating microstructure topology evolution of metals processed by cyclic SPD via the integration of DCC and FEA.
