The quest for the room-temperature optical transistor based on nonlinearities in single atoms or molecules is attracting a lot of attention.In this work,a single-photon emitter in cubic silicon carbide is verified tha...The quest for the room-temperature optical transistor based on nonlinearities in single atoms or molecules is attracting a lot of attention.In this work,a single-photon emitter in cubic silicon carbide is verified that can operate as an optical switch at room temperature under pulsed green laser illumination with a near-infrared pulsed laser as the control gate.We demonstrated an ultrafast and reversible optical modulation with a high photoluminescence intensity suppression ratio up to 97.9%and a response time as short as 287.9±5.7 ps.The current development provides insights for high-precision and ultrafast optical switches,with possibilities for integration with emerging electronic installations to realize more intelligent photoelectric integrated devices.展开更多
The synthesis,characterization,and theoretical studies of titanium-μ-N_(2) complexes with di-anionic guanidinate ligands were reported as the first example of its kind.Thus,with(Me_(3)Si)_(2)N-guanidinate ligands,the...The synthesis,characterization,and theoretical studies of titanium-μ-N_(2) complexes with di-anionic guanidinate ligands were reported as the first example of its kind.Thus,with(Me_(3)Si)_(2)N-guanidinate ligands,the mono-anionic guanidinate-supported titanium-μ-N2complex 1 was obtained.Then,reduction of 1 with potassium afforded the di-anionic guanidinate-supported titanium-μ-N_(2) complex 2 via cleavage of one N–Si bond of the(Me3Si)2N substituents in 1,changing the guanidinate ligands automatically from mono-anionic to di-anionic and remarkably lengthening the bond length of theμ-N_(2).Characteristic studies and DFT calculations were performed to reveal that the di-anionic guanidinate ligands stabilized the geometry of 2 and increased the charge density on the bridging dinitrogen.展开更多
Cobalt-bis(dinitrogen)complexes[LCo(N_(2))_(2)]−(3,4)with simple and commercially available bidentate phosphine ligands(L:Cy_(2)PCH_(2)CH_(2)PCy_(2))were synthesized and structurally characterized.Further N2 functiona...Cobalt-bis(dinitrogen)complexes[LCo(N_(2))_(2)]−(3,4)with simple and commercially available bidentate phosphine ligands(L:Cy_(2)PCH_(2)CH_(2)PCy_(2))were synthesized and structurally characterized.Further N2 functionalization by treating the complex 3b with i Pr_(3)SiCl afforded the first structurally characterized cobalt diazenido complex 5.These complexes 3–5 were found to be effective catalysts for the transformation of N2 into N(SiMe_(3))_(3).The electronic structure of the cobalt diazenido complex 5 is supported by quantum computational calculations based on stateof-the-art energy decomposition analysis(EDA)in conjunction with the natural orbitals for chemical valence(NOCV)method.展开更多
A series of structurally well-defined iron-dinitrogen complexes(LFe-N2)bearing cyclopentadienylphosphine ligands(L)were synthesized and analyzed by single-crystal X-ray structural analysis,IR/Raman spectra,magnetometr...A series of structurally well-defined iron-dinitrogen complexes(LFe-N2)bearing cyclopentadienylphosphine ligands(L)were synthesized and analyzed by single-crystal X-ray structural analysis,IR/Raman spectra,magnetometry,Mössbauer spectroscopy,and elemental analysis.The conversion relationship and the change of the spin states among the iron complexes with different valences were studied in detail.展开更多
Rare-earth metal boroxides are not only rare and of great synthetic challenge but also important theoretically due to their unrevealed bonding characteristics.In this paper,we report the synthesis,characterization,and...Rare-earth metal boroxides are not only rare and of great synthetic challenge but also important theoretically due to their unrevealed bonding characteristics.In this paper,we report the synthesis,characterization,and bonding characteristics of the 4f-block metal boroxide complexes ^(Mes)DAD_(2)LuOB(C_(6)F_(5))X(4-Lu,X=C_(6)F_(5);5-Lu,X=NC_(13)H_(10))with two chelating radical-anionic 1,4-diazabutadiene(DAD)ligands.The synthesis of 4-Lu or 5-Lu involved three steps,during which the radical-anionic DAD ligands could be kept stable:(1)the reaction of LuCl_(3),^(Mes)DAD,and potassium graphite(KC8)afforded the diradical rare-earth metal chloride ^(Mes)DAD_(2)LuCl·tetrahydrofuran(THF)(1-Lu);(2)the salt metathesis of 1-Lu with two alkali metal amides gave lutetium bis(diazabutadiene)amides 2-Lu or 3-Lu,respectively;and(3)2-Lu or 3-Lu reacted with B(C_(6)F_(5))_(3)·H_(2)O,resulting in the formation of rare-earth metal boroxides 4-Lu or 5-Lu.The radical-anionic nature of DAD ligands in these complexes were proven by their bond lengths and coordination modes in single-crystal structures.DFT calculations clearly show the bonding of 4-Lu can be divided into three major types of Lu-O orbital interactions,which can be categorized asσ-donation,π-donation,and d-π-conjugation.The triple Lu-O orbital interactions cooperatively make a Lu-O single bond and contribute to the linear Lu-O-B structure.展开更多
We investigate the strong coupling from 5,5’,6,6’-tetrachloro-1,1’-diethyl-3,3’-di(4-sulfobutyl)-benzimidazolocarbocyanine(TDBC)molecules near pure nano-triangular Ag prisms or Ag@Au hollow nanoshells.When TDBC mo...We investigate the strong coupling from 5,5’,6,6’-tetrachloro-1,1’-diethyl-3,3’-di(4-sulfobutyl)-benzimidazolocarbocyanine(TDBC)molecules near pure nano-triangular Ag prisms or Ag@Au hollow nanoshells.When TDBC molecules are deposited on pure Ag nanoprisms or Ag@Au hollow nanoshells with the plasmonic resonance peak,matching very closely with the absorption band of TDBC J-aggregates,obvious Rabi splitting can be observed due to the strong coupling regime.Meanwhile,the photoluminescence intensity decreased with the increasing of the temperature,verifying the decreasing plasmon-exciton coupling interaction in the higher temperature.Our experimental results are coincident with the simulation results calculated by finite-difference time-domain method.展开更多
基金National Key Research and Development Program of China(2021YFA1201503)National Natural Science Foundation of China(12274137)。
文摘The quest for the room-temperature optical transistor based on nonlinearities in single atoms or molecules is attracting a lot of attention.In this work,a single-photon emitter in cubic silicon carbide is verified that can operate as an optical switch at room temperature under pulsed green laser illumination with a near-infrared pulsed laser as the control gate.We demonstrated an ultrafast and reversible optical modulation with a high photoluminescence intensity suppression ratio up to 97.9%and a response time as short as 287.9±5.7 ps.The current development provides insights for high-precision and ultrafast optical switches,with possibilities for integration with emerging electronic installations to realize more intelligent photoelectric integrated devices.
基金supported by the Basic Science Center of Transformation Chemistry of Key Components of Air, the National Natural Science Foundation of China (21988101)supported by the High-performance Computing Platform of Peking University
文摘The synthesis,characterization,and theoretical studies of titanium-μ-N_(2) complexes with di-anionic guanidinate ligands were reported as the first example of its kind.Thus,with(Me_(3)Si)_(2)N-guanidinate ligands,the mono-anionic guanidinate-supported titanium-μ-N2complex 1 was obtained.Then,reduction of 1 with potassium afforded the di-anionic guanidinate-supported titanium-μ-N_(2) complex 2 via cleavage of one N–Si bond of the(Me3Si)2N substituents in 1,changing the guanidinate ligands automatically from mono-anionic to di-anionic and remarkably lengthening the bond length of theμ-N_(2).Characteristic studies and DFT calculations were performed to reveal that the di-anionic guanidinate ligands stabilized the geometry of 2 and increased the charge density on the bridging dinitrogen.
基金supported by the Basic Science Center of Transformation Chemistry of Key Components of Air,National Natural Science Foundation of China(no.21988101)M.Z.acknowledges China Postdoctoral Science Foundation(no.2019M650294)+1 种基金L.Z.acknowledges the financial support from NSFC(nos.21973044 and 21703099)Natural Science Foundation of Jiangsu Province for Youth(no.BK20170964)。
文摘Cobalt-bis(dinitrogen)complexes[LCo(N_(2))_(2)]−(3,4)with simple and commercially available bidentate phosphine ligands(L:Cy_(2)PCH_(2)CH_(2)PCy_(2))were synthesized and structurally characterized.Further N2 functionalization by treating the complex 3b with i Pr_(3)SiCl afforded the first structurally characterized cobalt diazenido complex 5.These complexes 3–5 were found to be effective catalysts for the transformation of N2 into N(SiMe_(3))_(3).The electronic structure of the cobalt diazenido complex 5 is supported by quantum computational calculations based on stateof-the-art energy decomposition analysis(EDA)in conjunction with the natural orbitals for chemical valence(NOCV)method.
基金supported by the Basic Science Center of Transformation Chemistry of Key Components of Air,National Natural Science Foundation of China(no.21988101).
文摘A series of structurally well-defined iron-dinitrogen complexes(LFe-N2)bearing cyclopentadienylphosphine ligands(L)were synthesized and analyzed by single-crystal X-ray structural analysis,IR/Raman spectra,magnetometry,Mössbauer spectroscopy,and elemental analysis.The conversion relationship and the change of the spin states among the iron complexes with different valences were studied in detail.
基金supported by the Natural Science Foundation of China(nos.21725201 and 21890721).
文摘Rare-earth metal boroxides are not only rare and of great synthetic challenge but also important theoretically due to their unrevealed bonding characteristics.In this paper,we report the synthesis,characterization,and bonding characteristics of the 4f-block metal boroxide complexes ^(Mes)DAD_(2)LuOB(C_(6)F_(5))X(4-Lu,X=C_(6)F_(5);5-Lu,X=NC_(13)H_(10))with two chelating radical-anionic 1,4-diazabutadiene(DAD)ligands.The synthesis of 4-Lu or 5-Lu involved three steps,during which the radical-anionic DAD ligands could be kept stable:(1)the reaction of LuCl_(3),^(Mes)DAD,and potassium graphite(KC8)afforded the diradical rare-earth metal chloride ^(Mes)DAD_(2)LuCl·tetrahydrofuran(THF)(1-Lu);(2)the salt metathesis of 1-Lu with two alkali metal amides gave lutetium bis(diazabutadiene)amides 2-Lu or 3-Lu,respectively;and(3)2-Lu or 3-Lu reacted with B(C_(6)F_(5))_(3)·H_(2)O,resulting in the formation of rare-earth metal boroxides 4-Lu or 5-Lu.The radical-anionic nature of DAD ligands in these complexes were proven by their bond lengths and coordination modes in single-crystal structures.DFT calculations clearly show the bonding of 4-Lu can be divided into three major types of Lu-O orbital interactions,which can be categorized asσ-donation,π-donation,and d-π-conjugation.The triple Lu-O orbital interactions cooperatively make a Lu-O single bond and contribute to the linear Lu-O-B structure.
基金supported by the National Key R&D Program of China(No.2017YFA0303403)the National Natural Science Foundation of China(Nos.11874015,12074012,11674099+2 种基金11722431)the Shanghai International CooperationProject(No.16520710600)the Program of Introducing Talents of Discipline to Universities(No.B12024)。
文摘We investigate the strong coupling from 5,5’,6,6’-tetrachloro-1,1’-diethyl-3,3’-di(4-sulfobutyl)-benzimidazolocarbocyanine(TDBC)molecules near pure nano-triangular Ag prisms or Ag@Au hollow nanoshells.When TDBC molecules are deposited on pure Ag nanoprisms or Ag@Au hollow nanoshells with the plasmonic resonance peak,matching very closely with the absorption band of TDBC J-aggregates,obvious Rabi splitting can be observed due to the strong coupling regime.Meanwhile,the photoluminescence intensity decreased with the increasing of the temperature,verifying the decreasing plasmon-exciton coupling interaction in the higher temperature.Our experimental results are coincident with the simulation results calculated by finite-difference time-domain method.
