Recent experimental advancements reported a chemical reaction between antimony and nitrogen under high temperature and high pressure,yielding crystalline antimony nitride(Sb_(3)N_(5))with an orthorhombic structure.Mot...Recent experimental advancements reported a chemical reaction between antimony and nitrogen under high temperature and high pressure,yielding crystalline antimony nitride(Sb_(3)N_(5))with an orthorhombic structure.Motivated by this statement,we calculate the stability,elastic properties,electronic properties and energy density of the Cmc2_(1) structure for pnictogen nitrides X_(3)N_(5)(X=P,As,Sb,and Bi)using first-principles calculations combined with particle swarm optimization algorithms.Calculations of formation enthalpies,elastic constants and phonon spectra show that P_(3)N_(5),As_(3)N_(5) and Sb_(3)N_(5) are thermodynamically,mechanically and kinetically stable at 35 GPa,whereas Bi_(3)N_(5) is mechanically and kinetically stable but thermodynamically unstable.The computed electronic density of states shows strong covalent bonding between the N atoms and the phosphorus group atoms in the four compounds,confirmed by the calculated electronic localization function.We also calculate the energy densities for Sb_(3)N_(5) and find it to be a potentially high-energy-density material.展开更多
Through the theoretical calculation of structural optimization, vibrational frequencies and atomization energies with one method of density functional theory （B3LYP） and two post- Hartree-Fock approaches （MP2, CCSD...Through the theoretical calculation of structural optimization, vibrational frequencies and atomization energies with one method of density functional theory （B3LYP） and two post- Hartree-Fock approaches （MP2, CCSD（T））, several stable isomers for new three pnictogen dianionic Sb4^2-, Bi4^2-, and （SbBi）2^2- species were determined. For two homoatomic Sb4^2- and Bi4^2- species, there are three stable isomers： square （D4h）, roof-shaped （C2v-1）, and C2v-2 structure with the square isomer being the ground state. For the heteroatomic dian- ionic （SbBi）2^2- species, there are also three stable isomers： rhombus （D2h）, roof-shaped （C1）, and C2v structures with the rhombic isomer being the ground state. The calculated NICS values show that nucleus-independent chemical shifts （NICS） values of roof-shaped isomers for Sb4^2-, Bi4^2-, and （SbBi）2^2- species are all negative, consequently indicating that these roof-shaped isomers possess aromaticities. NICS values for the planar ring isomers are all positive, suggesting that these three planar ring isomers have antiaromatic characters. The aromaticity for the two stable roof-shaped and square isomers are preliminarily explained and discussed with MO analysis.展开更多
Antimony-centered pnictogen bonds at the stibine level have provided access to good catalysis in solution and outstanding ion transport and catalysis in lipid bilayer membranes.Strengthened pnictogen bonds on the stib...Antimony-centered pnictogen bonds at the stibine level have provided access to good catalysis in solution and outstanding ion transport and catalysis in lipid bilayer membranes.Strengthened pnictogen bonds on the stiborane level have increased catalytic activity in solution to an extent attractive for use in practice.Thus,the debate was whether or not transport and catalysis in lipid bilayer membranes would equally increase fromσ-acidic stibines toσ-acidic stiboranes.The response,we report,is no.Experimental support for this conclusion covers a new set ofσ-acidic catecholatostiborane catalysts with bioinspired catecholates,supramolecular structural X-ray and computational data,transfer hydrogenation catalysis in water,micelles and membranes,and,of course,ion transport across lipid bilayers.Decreasing ion transport with increasing ion binding defined the inverted region in the Goldilocks principle.Our results placedσ-acidic stibines with weaker pnictogen bonds in the well-explored Goldilocks normal region.σ-acidic stiboranes,however,with their strong pnictogen bonds,provided unprecedented access to the Goldilocks inverted region and emerged as unique tools to generalize the Goldilocks principle from transport to catalysis and from membranes to micelles.The reported methods and results should be of general interest in the design and rationalization of supramolecular function in biphasic systems.展开更多
Pyridylphosphonium salts,which are readily available and air and thermally stable,have been used to effectively synthesize structurally diverse pyridines.Herein,we report the pnictogen bonding(PnB)enabled photoactivat...Pyridylphosphonium salts,which are readily available and air and thermally stable,have been used to effectively synthesize structurally diverse pyridines.Herein,we report the pnictogen bonding(PnB)enabled photoactivation of pyridylphosphonium salts with catalytic potassium carbonate to generate pyridyl radical for pyridine synthesis.Remarkably,this light-driven transformation allowed chiral pool synthesis with excellent chirality retention,giving a wide range of chiral selenium-containing pyridines.On the basis of our combined computational and experimental studies,we propose that the PnB between pyridylphosphonium salts and potassium carbonate enables access to the photoactive charge transfer complex,which is able to undergo single electron transfer to generate pyridyl radical for its transformation.展开更多
In the recent times sodium ion batteries(SIBs)have come to the forefront as an economic and resourceful alternative to lithium-ion batteries(LIBs)for powering portable electronic devices and large-scale grid storage.A...In the recent times sodium ion batteries(SIBs)have come to the forefront as an economic and resourceful alternative to lithium-ion batteries(LIBs)for powering portable electronic devices and large-scale grid storage.As the specific capacity,energy density and long cycle life of batteries depend upon the performance of anode materials;their quest is the ultimate need of the hour.Among the anode materials,the semimetallic pnictogens(As,Sb,Bi)and their compounds offer high gravimetric/volumetric capacities,but suffer from undesired volume expansion and inferior electrical conductivity.Herein,this paper reviews the recent progress in semimetallic pnictogens as alloying anodes and their compounds mainly as conversion-alloying anodes.Various debatable sodiation mechanisms(intercalation or alloying)have been presented with emphasis on in situ/ex situ advanced characterization methods well supported by theoretical modeling and calculations.The reviewed electrochemical reaction mechanisms,coherent structural designs and engineering provide a vital understanding of the electrochemical processes of Na^(+) ion storage.The existing challenges and perspectives are also presented,and several research directions are proposed from the aspects of special morphological design,employing conductive substrates,electrolyte additives and reducing particle size for technical and commercial success of SIBs.展开更多
基金the Young Talent Project of the Scientific Research Plan by the Hubei Provincial Department of Education(Grant No.Q20234301)the Guiding Project of the Scientific Research Plan by the Hubei Provincial Department of Education(Grant No.B2023222)+2 种基金the Natural Science Foundation of Hubei Province(Grant No.2022CFB527)the Scientific Research Project of Jingchu University of Technology(Grant Nos.YY202401,096201-5 Chin.Phys.B 33,096201(2024)YY202409,YY202207,and YB202212)the Open Research Projects of Jingchu University of Technology(Grant No.HX20240009).
文摘Recent experimental advancements reported a chemical reaction between antimony and nitrogen under high temperature and high pressure,yielding crystalline antimony nitride(Sb_(3)N_(5))with an orthorhombic structure.Motivated by this statement,we calculate the stability,elastic properties,electronic properties and energy density of the Cmc2_(1) structure for pnictogen nitrides X_(3)N_(5)(X=P,As,Sb,and Bi)using first-principles calculations combined with particle swarm optimization algorithms.Calculations of formation enthalpies,elastic constants and phonon spectra show that P_(3)N_(5),As_(3)N_(5) and Sb_(3)N_(5) are thermodynamically,mechanically and kinetically stable at 35 GPa,whereas Bi_(3)N_(5) is mechanically and kinetically stable but thermodynamically unstable.The computed electronic density of states shows strong covalent bonding between the N atoms and the phosphorus group atoms in the four compounds,confirmed by the calculated electronic localization function.We also calculate the energy densities for Sb_(3)N_(5) and find it to be a potentially high-energy-density material.
文摘Through the theoretical calculation of structural optimization, vibrational frequencies and atomization energies with one method of density functional theory （B3LYP） and two post- Hartree-Fock approaches （MP2, CCSD（T））, several stable isomers for new three pnictogen dianionic Sb4^2-, Bi4^2-, and （SbBi）2^2- species were determined. For two homoatomic Sb4^2- and Bi4^2- species, there are three stable isomers： square （D4h）, roof-shaped （C2v-1）, and C2v-2 structure with the square isomer being the ground state. For the heteroatomic dian- ionic （SbBi）2^2- species, there are also three stable isomers： rhombus （D2h）, roof-shaped （C1）, and C2v structures with the rhombic isomer being the ground state. The calculated NICS values show that nucleus-independent chemical shifts （NICS） values of roof-shaped isomers for Sb4^2-, Bi4^2-, and （SbBi）2^2- species are all negative, consequently indicating that these roof-shaped isomers possess aromaticities. NICS values for the planar ring isomers are all positive, suggesting that these three planar ring isomers have antiaromatic characters. The aromaticity for the two stable roof-shaped and square isomers are preliminarily explained and discussed with MO analysis.
基金supported by the University of Geneva,the National Centre of Competence in Research(NCCR)Molecular Systems Engineering,Switzerland(grant no.51NF40-205608)the Swiss National Science Foundation(NSF+3 种基金Swiss-ERC Advanced Grant TIMEUP,TMAG-2_209190Excellence Grant 200020204175)the Spain Ministry of Science,Innovation and Universities(MICIU/AEI of Spainproject PID2020-115637GB-I00 FEDER funds).
文摘Antimony-centered pnictogen bonds at the stibine level have provided access to good catalysis in solution and outstanding ion transport and catalysis in lipid bilayer membranes.Strengthened pnictogen bonds on the stiborane level have increased catalytic activity in solution to an extent attractive for use in practice.Thus,the debate was whether or not transport and catalysis in lipid bilayer membranes would equally increase fromσ-acidic stibines toσ-acidic stiboranes.The response,we report,is no.Experimental support for this conclusion covers a new set ofσ-acidic catecholatostiborane catalysts with bioinspired catecholates,supramolecular structural X-ray and computational data,transfer hydrogenation catalysis in water,micelles and membranes,and,of course,ion transport across lipid bilayers.Decreasing ion transport with increasing ion binding defined the inverted region in the Goldilocks principle.Our results placedσ-acidic stibines with weaker pnictogen bonds in the well-explored Goldilocks normal region.σ-acidic stiboranes,however,with their strong pnictogen bonds,provided unprecedented access to the Goldilocks inverted region and emerged as unique tools to generalize the Goldilocks principle from transport to catalysis and from membranes to micelles.The reported methods and results should be of general interest in the design and rationalization of supramolecular function in biphasic systems.
基金supported by grants from the National Natural Science Foundation of China(22101279,22001248)Fundamental Research Funds for the Central Universities,the University of the Chinese Academy of Sciences and Binzhou Institute of Technology,Weiqiao-UCAS Science and Technology Park.
文摘Pyridylphosphonium salts,which are readily available and air and thermally stable,have been used to effectively synthesize structurally diverse pyridines.Herein,we report the pnictogen bonding(PnB)enabled photoactivation of pyridylphosphonium salts with catalytic potassium carbonate to generate pyridyl radical for pyridine synthesis.Remarkably,this light-driven transformation allowed chiral pool synthesis with excellent chirality retention,giving a wide range of chiral selenium-containing pyridines.On the basis of our combined computational and experimental studies,we propose that the PnB between pyridylphosphonium salts and potassium carbonate enables access to the photoactive charge transfer complex,which is able to undergo single electron transfer to generate pyridyl radical for its transformation.
基金We thank the financial supports from the National Natural Science Foundation of China (No. 51774251)Hebei Natural Science Foundation for Distinguished Young Scholars (No. B2017203313)+2 种基金Hundred Excellent Innovative Talents Support Program in Hebei Province (No. SLRC2017057)Talent Engineering Training Funds of Hebei Province (No. A201802001)the opening project of the state key laboratory of Advanced Chemical Power Sources (No. SKL-ACPS-C-11).
文摘In the recent times sodium ion batteries(SIBs)have come to the forefront as an economic and resourceful alternative to lithium-ion batteries(LIBs)for powering portable electronic devices and large-scale grid storage.As the specific capacity,energy density and long cycle life of batteries depend upon the performance of anode materials;their quest is the ultimate need of the hour.Among the anode materials,the semimetallic pnictogens(As,Sb,Bi)and their compounds offer high gravimetric/volumetric capacities,but suffer from undesired volume expansion and inferior electrical conductivity.Herein,this paper reviews the recent progress in semimetallic pnictogens as alloying anodes and their compounds mainly as conversion-alloying anodes.Various debatable sodiation mechanisms(intercalation or alloying)have been presented with emphasis on in situ/ex situ advanced characterization methods well supported by theoretical modeling and calculations.The reviewed electrochemical reaction mechanisms,coherent structural designs and engineering provide a vital understanding of the electrochemical processes of Na^(+) ion storage.The existing challenges and perspectives are also presented,and several research directions are proposed from the aspects of special morphological design,employing conductive substrates,electrolyte additives and reducing particle size for technical and commercial success of SIBs.
