Herein,we present a versatile,metal-free protocol for arene C-H functionalization through arylsulfonium salts.A key discovery is that simple halogen anions(iodine,bromine)can act as electron donors when combined with ...Herein,we present a versatile,metal-free protocol for arene C-H functionalization through arylsulfonium salts.A key discovery is that simple halogen anions(iodine,bromine)can act as electron donors when combined with arylsulfonium salts,forming electron donor-acceptor complexes that generate aryl radicals upon visible light irradiation.This method enables the late-stage modification of complex bioactive and pharmaceutical compounds,facilitating arene iodination,bromination,phosphonylation,and arylation,which are challenging to achieve with comparable selectivity,diversity,and practicality using other approaches.Notably,the one-pot protocol for arene C-H iodination and C(sp^(2))-C(sp^(3))bond formation,along with successful gram-scale iodination and phosphonylation of boscalid,highlights the scalability and practical utility of this strategy.展开更多
A facile method for decarboxylative amination driven by the photoactivity of electron donor-acceptor(EDA)com-plexes assembled from iodide salts and redox-active esters has been proposed.A broad array of acyclic and cy...A facile method for decarboxylative amination driven by the photoactivity of electron donor-acceptor(EDA)com-plexes assembled from iodide salts and redox-active esters has been proposed.A broad array of acyclic and cyclic protected amines were readily synthesized without requiring exogenous transition-metal or photoredox catalysts.Moreover,this ap-proach facilitates late-stage functionalization of complex molecules and is amenable to continuous-flow process on gram scale.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
The relationship between the electronic structures of manganese nitrido complexes and the substituted ligands is investigated by using density functional theory.By designing a series of manganese nitrido complexes [Mn...The relationship between the electronic structures of manganese nitrido complexes and the substituted ligands is investigated by using density functional theory.By designing a series of manganese nitrido complexes [Mn(SalenR)N]+ with different para ring substituents(R = H,CH_3,NH_2,OCH_3,NMeF,etc) of the ancillary ligand,the properties of manganese-nitrogen bonds were compared for two kinds of electronic structures,of which the radical resides on metal center or the coordinated ring ligand.Our calculation shows that for R = H,CH_3 and NH_2,the [Mn(SalenR)N]+ complexes have a high-valent Mn(VI) center,and for R = OCH_3 and NMeF,the complexes represent a configuration where the radical delocalizes on the ligand.It is found that the relative energies of these two species depend on electronic properties of the substituent,originating from the intrinsic property of HOMO-LUMO gaps.展开更多
Electron paramagnetic resonance(EPR)or electron spin resonance(ESR)has been widely employed to characterize transition metal complexes.However,because of the high degree of complexity of transition metal EPR spectra,h...Electron paramagnetic resonance(EPR)or electron spin resonance(ESR)has been widely employed to characterize transition metal complexes.However,because of the high degree of complexity of transition metal EPR spectra,how to extract the underlying electronicstructure information inevitably poses a major challenge to beginners,in particular for systems with S>1/2.In fact,the physical principles of transition metal EPR have long been well-established and since 1970s a series of dedicated voluminous monographs have been published already.Not surprisingly,they are not appropriate stating points for novices to grasp a panorama of the profound theory prior to scrutinizing in-depth references.The present review aims to fill this gap to provide a perspective of transition metal EPR and unveil some peculiar subtleties thereof on the basis of our recent work.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
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
Studies on the electronic structure,molecular design,syntheses of some novel series of tetranuclear rare earth complexes in our laboratory have been reviewed.Spin-unrestricted localized INDO method was used to calcula...Studies on the electronic structure,molecular design,syntheses of some novel series of tetranuclear rare earth complexes in our laboratory have been reviewed.Spin-unrestricted localized INDO method was used to calculate the electronic structure and the chemical bonding in the typical rare earth cluster Sc[Sc_6Cl_(12)Co]was discussed.展开更多
This paper investigates the infrared absorption spectra of oxygen-related complexes in silicon crystals irradiated with electron (1.5 MeV) at 360 K.Two groups of samples with low [Oi] = 6.9 x 10^17 cm^-3 and high [O...This paper investigates the infrared absorption spectra of oxygen-related complexes in silicon crystals irradiated with electron (1.5 MeV) at 360 K.Two groups of samples with low [Oi] = 6.9 x 10^17 cm^-3 and high [Oi] = 1.06 x 10^18 cm^-3 were used.We found that the concentration of the VO pairs have different behaviour to the annealing temperature in different concentration of oxygen specimen,it is hardly changed in the higher concentration of oxygen specimen.It was also found that the concentration of VO2 in lower concentration of oxygen specimen gets to maximum at 450 ℃ and then dissapears at 500 ℃,accompanied with the appearing of VO3. For both kinds of specimens,the concentration of VO3 reachs to maximum at 550 ℃ and does not disappear completely at 600 ℃.展开更多
The electronic structure and electronic absorption spectra of binuclear Au(Ⅰ) complexes with bidentate phophines and a bidentate ylid ligand have been studied using quasirelativistic pseudopotential ab initio cal...The electronic structure and electronic absorption spectra of binuclear Au(Ⅰ) complexes with bidentate phophines and a bidentate ylid ligand have been studied using quasirelativistic pseudopotential ab initio calculations at the HF and MP2 levels by the LANL2DZ basis sets. The electronic properties of the spectral transition and Au(Ⅰ)—Au(Ⅰ) interaction were also discussed.展开更多
The electronic structures of several dinuclears and trinuclears of molybdenum containing thiolates complexes have been calculated by quantum chemistry SCC-DV-Xa method, and the reactivity of complexes has been analy...The electronic structures of several dinuclears and trinuclears of molybdenum containing thiolates complexes have been calculated by quantum chemistry SCC-DV-Xa method, and the reactivity of complexes has been analyzed in terms of the molecular orbital energy level diagrams, orbital characters and charge populations.展开更多
l,l'-biisoquinoline can coordinate with ruthenfum(Ⅱ) to form a new series of mononuclear complexes and the electronic absorption of these complexes were measured and reasonably assigned.
A series of lanthanide complexes LnCl_3·L(Ln=La,Pr,Nd;L=15-C-5 or 18-C-6)have been synthesized and their molecular configuration,electronic structure and bond character have been studied by XPS and quantum chemic...A series of lanthanide complexes LnCl_3·L(Ln=La,Pr,Nd;L=15-C-5 or 18-C-6)have been synthesized and their molecular configuration,electronic structure and bond character have been studied by XPS and quantum chemical calculation.The calculated results are in good agreement with that obtained in the experiments.Three Cl atoms are on the same side of Ln in LnCl_3·15-C-5 and the crown ring on the other side.forming a complex molecule with coordination number 8.LnCl_3·15-C-5 is easily hygroscopic in air because of its unsaturated coordination,which differs sharply from the stable Ln(NO_3)_3·15-C-5 com- plex of coordination number 11.The HOMO and neighboring occupied MOs are composed of Cl 3p and O2p, and the LUMO and neighboring unoccupied MOs are composed of Ln orbitals.The level structure easily pro- duces Ln3d satellite in XPS caused by L→Ln charge transfer transition.Due to the coordination,the absolute values of the charge are decreased at Ln and O atoms,but increased at Cl atoms,which is in agreement with XPS results.展开更多
In this study, the first raw transition metals from V to Co complexes with benzene-1,2-dithiolate (L2-) ligand have been studied theoretically to elucidate the geometry, electronic structure and spectroscopic properti...In this study, the first raw transition metals from V to Co complexes with benzene-1,2-dithiolate (L2-) ligand have been studied theoretically to elucidate the geometry, electronic structure and spectroscopic properties of the complexes. Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TD-DFT) methods have been used. The ground state geometries, binding energies, spectral properties (UV-vis), frontier molecular orbitals (FMOs) analysis, charge analysis and natural bond orbital (NBO) have been investigated. The geometrical parameters are in good agreement with the available experimental data. The metal-ligand binding energies are 1 order of magnitude larger than the physisorption energy of a benzene-1, 2-dthiolate molecule on a metallic surface. The electronic structures of the first raw transition metal series from V to Co have been elucidated by UV-vis spectroscopic using DFT calculations. In accordance with experiment the calculated electronic spectra of these tris complexes show bands at 522, 565, 559, 546 and 863 nm for V3+, Cr3+, Mn3+, Fe3+ and Co3+ respectively which are mainly attributed to ligand to metal charge transfer (LMCT) transitions. The electronic properties analysis shows that the highest occupied molecular orbital (HOMO) is mainly centered on metal coordinated sulfur atoms whereas the lowest unoccupied molecular orbital (LUMO) is mainly located on the metal surface. From calculation of intramolecular interactions and electron delocalization by natural bond orbital (NBO) analysis, the stability of the complexes was estimated. The NBO results showed significant charge transfer from sulfur to central metal ions in the complexes, as well as to the benzene. The calculated charges on metal ions are also reported at various charge schemes. The calculations show encouraging agreement with the available experimental data.展开更多
A model of electronic intersupplemental states was presented for calculating the d orbital energies of a distorted octahedral low spin ( S =1/2) n d 5(t 5 2, 2T 2)(n=3, 4, 5) multielectron system...A model of electronic intersupplemental states was presented for calculating the d orbital energies of a distorted octahedral low spin ( S =1/2) n d 5(t 5 2, 2T 2)(n=3, 4, 5) multielectron system, and the 6 dimensional eigenmatrices of two new types in real and complex orbital representations were derived from this electron model forth. In comparison with real and complex orbital methods offered by the hole model, the real and complex orbital methods reported in this paper not only could give directly all the electronic structure parameters for the n d 5(t 5 2, 2T 2) multielectron system, but also showed many other new advantages such as standardization in theory, systematization in method, agreement in calculation and so on.展开更多
The changes of chlorophyll_protein complexes and photosynthetic activities of chloroplast isolated from lotus ( Nelumbo nucifera Gaertn.) seeds germinating under illumination were studied. SDS PAGE analysis of c...The changes of chlorophyll_protein complexes and photosynthetic activities of chloroplast isolated from lotus ( Nelumbo nucifera Gaertn.) seeds germinating under illumination were studied. SDS PAGE analysis of chlorophyll_protein complexes showed that there was only the light harvesting chlorophyll a/b protein complex from PSⅡ (LHCⅡ) precursor in chloroplast from lotus seeds germinated for 2 to 6 days, while LHC Ⅱ 1, and the chlorophyll_protein complex of PSⅠ (CPⅠ) appeared on the 8th day of germination and PSⅡ reaction center complex appeared later. Studies on the polypeptides composition of the chloroplast revealed the following results: 1) Small amount of the 27 kD polypeptide was synthesized in invisible light; 2) The 30 kD polypeptide existed previously in the plumules of the dry seeds; 3) The amount of the 30 kD polypeptide was more than any other polypeptides before germination and decreased gradually throughout germination, while the 27 kD polypeptide changed in the opposite way; 4) In the process of germination, measurement of the electron transport rate and the fluorescence induction kinetics at room temperature showed that PSⅡ activities and efficiency of primary light energy transformation were only experimentally measurable after 7 days of germination and gradually increased afterwards. At the same time, the chl a/b ratio rose from the lower value to normal; 5) The changes of chloroplast membrane components and its functions are concomitant in concert with that of the ultrastructure of chloroplast membranes during germination, as shown in our earlier work . The results have proved again that a different developmental pathway of chloroplast is likely to exist in the lotus plumules, which might provide an important clue for N. nucifera in having an unique position in the phylogeny of the angiosperm.展开更多
A lipid_depleted cytochrome b 6f (Cyt b 6f) preparation was obtained from spinach (Spinacia oleracea L.) chloroplasts. Upon reconstitution of this preparation with the membrane lipids purified from spinach thylakoid...A lipid_depleted cytochrome b 6f (Cyt b 6f) preparation was obtained from spinach (Spinacia oleracea L.) chloroplasts. Upon reconstitution of this preparation with the membrane lipids purified from spinach thylakoid, the effects of different membrane lipids on the electron transfer activity were studied. The results show that the electron transfer activity of Cyt b 6f is obviously stimulated to different extents, respectively, by monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), phosphatidylcholine (PC), phosphatidylglycerol (PG) and sulfoquinovosyldiacylglycerol (SQDG), and that the extents of stimulation may be closely related to the charge of the membrane lipids. The stimulation of non_charged lipids (MGDG, DGDG) and neutrally_charged lipid (PC) was high with a maximum enhancement of 89%, 75% and 77%, respectively; but the stimulation of two kinds of negatively_charged lipid (PG and SQDG) was relatively low with a maximum enhancement of 43% and 26%, respectively.展开更多
The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine...The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine, phen=l,10-phenanthroline, and X=-C-=CH (1), X=Cl (2), X-CN (3)) were investigated theoretically using the density functional theory method. The ground and excited state geometries have been fully optimized at the B3LYP/LanL2DZ and UB3LYP/LanL2DZ levels, respectively. The absorption and emission spectra of the com- plexes in CHaCN solutions were calculated by time-dependent density functional theory with the PCM solvent model. The calculated bond lengths of Ru-C, Ru-N, and Ru-Cl in the ground state agree well with the corresponding experimental results. The highest occupied molecular orbital were dominantly localized on the Ru atom and monodentate X ligand for 1 and 2, Ru atom and terpy ligand for a, while the lowest unoccupied molecular orbital were π*(terpy) type orbital. Therefore, the lowest-energy absorptions of 1 and 2 at 688 and 631 nln are attributed to a dyz (Ru)+Tr/p(X)--π* (terpy) transition with MLCT/XLCT (metal-to-ligand charge transfer/X ligand to terpy ligand charge transfer) character, whereas that of 3 at 529 nm is related to a dyz (Ru)+π(terpy)-π* (terpy) transition with MLCT and ILCT transition character. The calculated phosphorescence of three complexes at 1011 nm (1), 913 nm (2), and 838 nm (3) have similar transition properties to that of the lowest-lying absorption. It is shown that the lowest lying absorptions and emissions transition character of these Ru(II) complexes can be tuned by changing the electron-withdrawing ability of the monodentate ligand.展开更多
Large,3D curved electronics are a trend of the microelectronic industry due to their unique ability to conformally coexist with complex surfaces while retaining the electronic functions of 2D planar integrated circuit...Large,3D curved electronics are a trend of the microelectronic industry due to their unique ability to conformally coexist with complex surfaces while retaining the electronic functions of 2D planar integrated circuit technologies.However,these curved electronics present great challenges to the fabrication processes.Here,we propose a reconfigurable,mask-free,conformal fabrication strategy with a robot-like system,called robotized‘transfer-and-jet’printing,to assemble diverse electronic devices on complex surfaces.This novel method is a ground-breaking advance with the unique capability to integrate rigid chips,flexible electronics,and conformal circuits on complex surfaces.Critically,each process,including transfer printing,inkjet printing,and plasma treating,are mask-free,digitalized,and programmable.The robotization techniques,including measurement,surface reconstruction and localization,and path programming,break through the fundamental constraints of 2D planar microfabrication in the context of geometric shape and size.The transfer printing begins with the laser lift-off of rigid chips or flexible electronics from donor substrates,which are then transferred onto a curved surface via a dexterous robotic palm.Then the robotic electrohydrodynamic printing directly writes submicrometer structures on the curved surface.Their permutation and combination allow versatile conformal microfabrication.Finally,robotized hybrid printing is utilized to successfully fabricate a conformal heater and antenna on a spherical surface and a flexible smart sensing skin on a winged model,where the curved circuit,flexible capacitive and piezoelectric sensor arrays,and rigid digital–analog conversion chips are assembled.Robotized hybrid printing is an innovative printing technology,enabling additive,noncontact and digital microfabrication for 3D curved electronics.展开更多
基金supported by the National Natural Science Foundation of China(22101272)the National Youth Talent Programthe Research Start-Up Funds of Hefei University of Technology。
文摘Herein,we present a versatile,metal-free protocol for arene C-H functionalization through arylsulfonium salts.A key discovery is that simple halogen anions(iodine,bromine)can act as electron donors when combined with arylsulfonium salts,forming electron donor-acceptor complexes that generate aryl radicals upon visible light irradiation.This method enables the late-stage modification of complex bioactive and pharmaceutical compounds,facilitating arene iodination,bromination,phosphonylation,and arylation,which are challenging to achieve with comparable selectivity,diversity,and practicality using other approaches.Notably,the one-pot protocol for arene C-H iodination and C(sp^(2))-C(sp^(3))bond formation,along with successful gram-scale iodination and phosphonylation of boscalid,highlights the scalability and practical utility of this strategy.
文摘A facile method for decarboxylative amination driven by the photoactivity of electron donor-acceptor(EDA)com-plexes assembled from iodide salts and redox-active esters has been proposed.A broad array of acyclic and cyclic protected amines were readily synthesized without requiring exogenous transition-metal or photoredox catalysts.Moreover,this ap-proach facilitates late-stage functionalization of complex molecules and is amenable to continuous-flow process on gram scale.
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supported by the Project of National Natural Science Foundation of China(No.21573237,21603227,21403242,21703246)Natural Science Foundation of Fujian Province(2017J05032)
文摘The relationship between the electronic structures of manganese nitrido complexes and the substituted ligands is investigated by using density functional theory.By designing a series of manganese nitrido complexes [Mn(SalenR)N]+ with different para ring substituents(R = H,CH_3,NH_2,OCH_3,NMeF,etc) of the ancillary ligand,the properties of manganese-nitrogen bonds were compared for two kinds of electronic structures,of which the radical resides on metal center or the coordinated ring ligand.Our calculation shows that for R = H,CH_3 and NH_2,the [Mn(SalenR)N]+ complexes have a high-valent Mn(VI) center,and for R = OCH_3 and NMeF,the complexes represent a configuration where the radical delocalizes on the ligand.It is found that the relative energies of these two species depend on electronic properties of the substituent,originating from the intrinsic property of HOMO-LUMO gaps.
基金the financial support from Chinese Academy of Sciences,National Science Foundation of China(92161204)Max-Planck Society。
文摘Electron paramagnetic resonance(EPR)or electron spin resonance(ESR)has been widely employed to characterize transition metal complexes.However,because of the high degree of complexity of transition metal EPR spectra,how to extract the underlying electronicstructure information inevitably poses a major challenge to beginners,in particular for systems with S>1/2.In fact,the physical principles of transition metal EPR have long been well-established and since 1970s a series of dedicated voluminous monographs have been published already.Not surprisingly,they are not appropriate stating points for novices to grasp a panorama of the profound theory prior to scrutinizing in-depth references.The present review aims to fill this gap to provide a perspective of transition metal EPR and unveil some peculiar subtleties thereof on the basis of our recent work.
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(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Project supported by The National Natural Science Foundation of China and Science and Technology Foundation of State Education Commision of China
文摘Studies on the electronic structure,molecular design,syntheses of some novel series of tetranuclear rare earth complexes in our laboratory have been reviewed.Spin-unrestricted localized INDO method was used to calculate the electronic structure and the chemical bonding in the typical rare earth cluster Sc[Sc_6Cl_(12)Co]was discussed.
基金Project supported by the National Natural Science Foundation of China (Grant No 50872028)Natural Science Foundation of Hebei Province of China (Grant Nos E200500048 and E2008000079)Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No 20050080006)
文摘This paper investigates the infrared absorption spectra of oxygen-related complexes in silicon crystals irradiated with electron (1.5 MeV) at 360 K.Two groups of samples with low [Oi] = 6.9 x 10^17 cm^-3 and high [Oi] = 1.06 x 10^18 cm^-3 were used.We found that the concentration of the VO pairs have different behaviour to the annealing temperature in different concentration of oxygen specimen,it is hardly changed in the higher concentration of oxygen specimen.It was also found that the concentration of VO2 in lower concentration of oxygen specimen gets to maximum at 450 ℃ and then dissapears at 500 ℃,accompanied with the appearing of VO3. For both kinds of specimens,the concentration of VO3 reachs to maximum at 550 ℃ and does not disappear completely at 600 ℃.
文摘The electronic structure and electronic absorption spectra of binuclear Au(Ⅰ) complexes with bidentate phophines and a bidentate ylid ligand have been studied using quasirelativistic pseudopotential ab initio calculations at the HF and MP2 levels by the LANL2DZ basis sets. The electronic properties of the spectral transition and Au(Ⅰ)—Au(Ⅰ) interaction were also discussed.
文摘The electronic structures of several dinuclears and trinuclears of molybdenum containing thiolates complexes have been calculated by quantum chemistry SCC-DV-Xa method, and the reactivity of complexes has been analyzed in terms of the molecular orbital energy level diagrams, orbital characters and charge populations.
文摘l,l'-biisoquinoline can coordinate with ruthenfum(Ⅱ) to form a new series of mononuclear complexes and the electronic absorption of these complexes were measured and reasonably assigned.
文摘A series of lanthanide complexes LnCl_3·L(Ln=La,Pr,Nd;L=15-C-5 or 18-C-6)have been synthesized and their molecular configuration,electronic structure and bond character have been studied by XPS and quantum chemical calculation.The calculated results are in good agreement with that obtained in the experiments.Three Cl atoms are on the same side of Ln in LnCl_3·15-C-5 and the crown ring on the other side.forming a complex molecule with coordination number 8.LnCl_3·15-C-5 is easily hygroscopic in air because of its unsaturated coordination,which differs sharply from the stable Ln(NO_3)_3·15-C-5 com- plex of coordination number 11.The HOMO and neighboring occupied MOs are composed of Cl 3p and O2p, and the LUMO and neighboring unoccupied MOs are composed of Ln orbitals.The level structure easily pro- duces Ln3d satellite in XPS caused by L→Ln charge transfer transition.Due to the coordination,the absolute values of the charge are decreased at Ln and O atoms,but increased at Cl atoms,which is in agreement with XPS results.
文摘In this study, the first raw transition metals from V to Co complexes with benzene-1,2-dithiolate (L2-) ligand have been studied theoretically to elucidate the geometry, electronic structure and spectroscopic properties of the complexes. Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TD-DFT) methods have been used. The ground state geometries, binding energies, spectral properties (UV-vis), frontier molecular orbitals (FMOs) analysis, charge analysis and natural bond orbital (NBO) have been investigated. The geometrical parameters are in good agreement with the available experimental data. The metal-ligand binding energies are 1 order of magnitude larger than the physisorption energy of a benzene-1, 2-dthiolate molecule on a metallic surface. The electronic structures of the first raw transition metal series from V to Co have been elucidated by UV-vis spectroscopic using DFT calculations. In accordance with experiment the calculated electronic spectra of these tris complexes show bands at 522, 565, 559, 546 and 863 nm for V3+, Cr3+, Mn3+, Fe3+ and Co3+ respectively which are mainly attributed to ligand to metal charge transfer (LMCT) transitions. The electronic properties analysis shows that the highest occupied molecular orbital (HOMO) is mainly centered on metal coordinated sulfur atoms whereas the lowest unoccupied molecular orbital (LUMO) is mainly located on the metal surface. From calculation of intramolecular interactions and electron delocalization by natural bond orbital (NBO) analysis, the stability of the complexes was estimated. The NBO results showed significant charge transfer from sulfur to central metal ions in the complexes, as well as to the benzene. The calculated charges on metal ions are also reported at various charge schemes. The calculations show encouraging agreement with the available experimental data.
文摘A model of electronic intersupplemental states was presented for calculating the d orbital energies of a distorted octahedral low spin ( S =1/2) n d 5(t 5 2, 2T 2)(n=3, 4, 5) multielectron system, and the 6 dimensional eigenmatrices of two new types in real and complex orbital representations were derived from this electron model forth. In comparison with real and complex orbital methods offered by the hole model, the real and complex orbital methods reported in this paper not only could give directly all the electronic structure parameters for the n d 5(t 5 2, 2T 2) multielectron system, but also showed many other new advantages such as standardization in theory, systematization in method, agreement in calculation and so on.
文摘The changes of chlorophyll_protein complexes and photosynthetic activities of chloroplast isolated from lotus ( Nelumbo nucifera Gaertn.) seeds germinating under illumination were studied. SDS PAGE analysis of chlorophyll_protein complexes showed that there was only the light harvesting chlorophyll a/b protein complex from PSⅡ (LHCⅡ) precursor in chloroplast from lotus seeds germinated for 2 to 6 days, while LHC Ⅱ 1, and the chlorophyll_protein complex of PSⅠ (CPⅠ) appeared on the 8th day of germination and PSⅡ reaction center complex appeared later. Studies on the polypeptides composition of the chloroplast revealed the following results: 1) Small amount of the 27 kD polypeptide was synthesized in invisible light; 2) The 30 kD polypeptide existed previously in the plumules of the dry seeds; 3) The amount of the 30 kD polypeptide was more than any other polypeptides before germination and decreased gradually throughout germination, while the 27 kD polypeptide changed in the opposite way; 4) In the process of germination, measurement of the electron transport rate and the fluorescence induction kinetics at room temperature showed that PSⅡ activities and efficiency of primary light energy transformation were only experimentally measurable after 7 days of germination and gradually increased afterwards. At the same time, the chl a/b ratio rose from the lower value to normal; 5) The changes of chloroplast membrane components and its functions are concomitant in concert with that of the ultrastructure of chloroplast membranes during germination, as shown in our earlier work . The results have proved again that a different developmental pathway of chloroplast is likely to exist in the lotus plumules, which might provide an important clue for N. nucifera in having an unique position in the phylogeny of the angiosperm.
基金The State Key Basic Research and Development Plan(G1998010100)Innovative Foundation of Laboratory of Photosynthesis Basic Research Insitute of Botany,The Chinese Academy of Sciences
文摘A lipid_depleted cytochrome b 6f (Cyt b 6f) preparation was obtained from spinach (Spinacia oleracea L.) chloroplasts. Upon reconstitution of this preparation with the membrane lipids purified from spinach thylakoid, the effects of different membrane lipids on the electron transfer activity were studied. The results show that the electron transfer activity of Cyt b 6f is obviously stimulated to different extents, respectively, by monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), phosphatidylcholine (PC), phosphatidylglycerol (PG) and sulfoquinovosyldiacylglycerol (SQDG), and that the extents of stimulation may be closely related to the charge of the membrane lipids. The stimulation of non_charged lipids (MGDG, DGDG) and neutrally_charged lipid (PC) was high with a maximum enhancement of 89%, 75% and 77%, respectively; but the stimulation of two kinds of negatively_charged lipid (PG and SQDG) was relatively low with a maximum enhancement of 43% and 26%, respectively.
文摘The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine, phen=l,10-phenanthroline, and X=-C-=CH (1), X=Cl (2), X-CN (3)) were investigated theoretically using the density functional theory method. The ground and excited state geometries have been fully optimized at the B3LYP/LanL2DZ and UB3LYP/LanL2DZ levels, respectively. The absorption and emission spectra of the com- plexes in CHaCN solutions were calculated by time-dependent density functional theory with the PCM solvent model. The calculated bond lengths of Ru-C, Ru-N, and Ru-Cl in the ground state agree well with the corresponding experimental results. The highest occupied molecular orbital were dominantly localized on the Ru atom and monodentate X ligand for 1 and 2, Ru atom and terpy ligand for a, while the lowest unoccupied molecular orbital were π*(terpy) type orbital. Therefore, the lowest-energy absorptions of 1 and 2 at 688 and 631 nln are attributed to a dyz (Ru)+Tr/p(X)--π* (terpy) transition with MLCT/XLCT (metal-to-ligand charge transfer/X ligand to terpy ligand charge transfer) character, whereas that of 3 at 529 nm is related to a dyz (Ru)+π(terpy)-π* (terpy) transition with MLCT and ILCT transition character. The calculated phosphorescence of three complexes at 1011 nm (1), 913 nm (2), and 838 nm (3) have similar transition properties to that of the lowest-lying absorption. It is shown that the lowest lying absorptions and emissions transition character of these Ru(II) complexes can be tuned by changing the electron-withdrawing ability of the monodentate ligand.
基金The authors acknowledge support from the National Nat-ural Science Foundation of China(51635007,51925503,51705179)Natural Science Foundation of Hubei Province of China(2020CFA028).
文摘Large,3D curved electronics are a trend of the microelectronic industry due to their unique ability to conformally coexist with complex surfaces while retaining the electronic functions of 2D planar integrated circuit technologies.However,these curved electronics present great challenges to the fabrication processes.Here,we propose a reconfigurable,mask-free,conformal fabrication strategy with a robot-like system,called robotized‘transfer-and-jet’printing,to assemble diverse electronic devices on complex surfaces.This novel method is a ground-breaking advance with the unique capability to integrate rigid chips,flexible electronics,and conformal circuits on complex surfaces.Critically,each process,including transfer printing,inkjet printing,and plasma treating,are mask-free,digitalized,and programmable.The robotization techniques,including measurement,surface reconstruction and localization,and path programming,break through the fundamental constraints of 2D planar microfabrication in the context of geometric shape and size.The transfer printing begins with the laser lift-off of rigid chips or flexible electronics from donor substrates,which are then transferred onto a curved surface via a dexterous robotic palm.Then the robotic electrohydrodynamic printing directly writes submicrometer structures on the curved surface.Their permutation and combination allow versatile conformal microfabrication.Finally,robotized hybrid printing is utilized to successfully fabricate a conformal heater and antenna on a spherical surface and a flexible smart sensing skin on a winged model,where the curved circuit,flexible capacitive and piezoelectric sensor arrays,and rigid digital–analog conversion chips are assembled.Robotized hybrid printing is an innovative printing technology,enabling additive,noncontact and digital microfabrication for 3D curved electronics.