The magnetization dynamics of lanthanide coordination compounds are fundamentals governing their potential applications such as information storage or molecular switches.Herein,two two-dimensional coordination polymer...The magnetization dynamics of lanthanide coordination compounds are fundamentals governing their potential applications such as information storage or molecular switches.Herein,two two-dimensional coordination polymers[Er(CA)_(1.5)(bpy)(DMF)]_(n)(1)and[Er(CA)_(1.5)(phen)(DMF)]_(n)(2)(H_(2)CA=2,5-dichloro-3,6-dihydroxy-p-quinone,bpy=2,2'-bipyridine,phen=1,10-phenanthroline)were synthesized and fully characterized.By the irradiation of ultraviolet light,1 and 2 were converted to la and 2a which contain light-generated radicals,inducing an increase ofχ_(MT)at room temperature.A detailed study of the dynamic magnetic property shows that the magnetization dynamics observed for 1 and la are dominated by Raman process,but Orbach and Raman processes are observed in 2 and 2a.The structural factors influencing the magnetic properties of this photomagnetic system are discussed.展开更多
The urgent imperative for carbon-neutral chemical production has accelerated the development of solardriven catalytic technologies that convert abundant C_(1) feedstocks(CO_(2) and CH_(4))into value-added C_(2+)molecu...The urgent imperative for carbon-neutral chemical production has accelerated the development of solardriven catalytic technologies that convert abundant C_(1) feedstocks(CO_(2) and CH_(4))into value-added C_(2+)molecules.Standalone photocatalysis remains constrained by rapid chargecarrier recombination and poor C-C coupling selectivity.This review critically examines multi-field-coupled catalysis-a transformative paradigm synergistically integrating solar energy with auxiliary thermal,electric,and magnetic fields.Through mechanistic dissection of photothermal,photoelectrochemical,and photomagnetic field cooperativities,it is summarized that thermal gradients attenuate phonon scattering to enhance charge-carrier drift mobility while vibrationally stabilizing reactive intermediates,electric potentials drive vectorial charge transport via Coulomb-forcedirected separation and band alignment,and magnetic fields modulate spin-selective electron transfer through Zeeman splitting-mediated polarization to boost reaction specificity.This synergistic multi-field integration circumvents intrinsic limitations of single-mode photocatalysis by collectively reconfiguring reaction coordinates for selective C-C coupling.We further address persistent challenges in resolving ultrafast interfacial charge-transfer dynamics,scaling integrated field reactors for industrial deployment,and advancing in situ operando characterization of multiscale processes.Strategic research priorities are proposed to advance sustainable multifield-coupled catalytic production of fuels and platform chemicals.展开更多
A newly synthesized photomagnet based on a cyanido-bridged Co-W assembly,[{Co(isoquinoline)_(4)}_(3){W(CN)_(8)}_(2)]·_(2)EtOH(CoWisoq),exhibits a controllable photoinduced(PI)phase with a metamagnetic behavior.Th...A newly synthesized photomagnet based on a cyanido-bridged Co-W assembly,[{Co(isoquinoline)_(4)}_(3){W(CN)_(8)}_(2)]·_(2)EtOH(CoWisoq),exhibits a controllable photoinduced(PI)phase with a metamagnetic behavior.The PI phase shows a transition from paramagnetic to ferromagnetic with a coercive field of 550 Oe at 2 K.It has a monoclinic(P21/n)crystal structure and is comprised of two-dimensional cyanido-bridged Co-W coordination layers with two crystallographically independent Co sites(Co1,Co2)and one W site.Both Co sites adopt a pseudo-octahedral six-coordinated geometry involving four isoquinoline and two cyanide ligands.π-πinteractions are induced at half of the isoquinoline ligands in Co1 and all of those in Co2 sites,suggesting that the coordination environment at the Co1 site has structural flexibility.CoWisoq displays a thermal phase transition around 140 K with a small thermal hysteresis due to the charge transfer-induced spin transition between Co^(Ⅱ)-W^(Ⅴ) of the high temperature(HT)phase and Co ^(Ⅲ)-W^(Ⅳ) of the low temperature(LT)phase.This charge transfer,which is also responsible for a drastic color change between purple(HT)and yellow(LT),involves only the structurally flexible Co1 sites.The ligand field,which is composed of four isoquinoline and two cyanide ligands,contributes to a unique metal-to-metal charge transfer absorption band of the LT phase at 1025 nm.Irradiation of the LT phase with near-infrared light produces a PI phase with the CoII-WV state.展开更多
The pursuit of spin crossover(SCO)materials with photoswitchable multistability is driven by fascinating perspectives toward light-response switches and opto-magnetic memory devices.Herein,we report a 3D Hofmann-type ...The pursuit of spin crossover(SCO)materials with photoswitchable multistability is driven by fascinating perspectives toward light-response switches and opto-magnetic memory devices.Herein,we report a 3D Hofmann-type metal–organic framework[Fe(bpn){Ag(CN)_(2)}_(2)]·1.5(Fnaph)(bpn=1,4-di(pyridin-4-yl)naphthalene,Fnaph=1-fluoronaphthalene),which displays an incomplete two-step SCO behaviour.The asymmetric host–vip interactions induce an intermediate HS–LS state at low temperature.Photomagnetic measurements exhibited an extremely rare bidirectional light-induced excited spin-state trapping(LIESST)effect with green and near-IR light irradiation,in which both metastable HS*and hidden LS*states were revealed at 10 K.The light-induced tristability paves the way for designing optomagnetic memory devices.展开更多
The crystal engineering of octacyanidomolybdate(Ⅳ)ions and copper(Ⅱ)complexes with two types of chelating ligands:multidentate blocking ligand,tren=(tris(2 aminoethyl)amine),and bidentate ligand capable of forming u...The crystal engineering of octacyanidomolybdate(Ⅳ)ions and copper(Ⅱ)complexes with two types of chelating ligands:multidentate blocking ligand,tren=(tris(2 aminoethyl)amine),and bidentate ligand capable of forming unusual organic bridges,tn=1,3-diaminopropane,resulted in the formation of{[Cu(tren)]2(μ-tn)}·[Mo(CN)8]·7.5H2O(1)and{[Cu(tren)]2(μ-tn)}·[Mo(CN)8]·{[Cu(tren)]2[Mo(CN)8]}·9H2O(2).The crystal structure of 1 comprises isolated anions[Mo(CN)8]4-wrapped with charge-compensating units{[Cu(tren)]2(μ-tn)}^(4+)stabilised by extensive H-bond networks.Compound 2 forms alternating layers consisting of the same ions as 1 and neutral cyanido-bridged V-shaped trinuclear molecules{[Cu(tren)]2[Mo(CN)8]}.Additionally,two previously reported V-shaped trinuclear reference systems were synthesised:[Cu(tn)2]2[Mo(CN)_(8)]·2H_(2)O(3)and[Cu(tren)]2[Mo(CN)8]·5.25H2O(4).UV–Vis–NIR absorption spectroscopy,supported by quantum chemical calculations(DFT and TD-DFT),confirmed the presence of Mo(Ⅳ)to Cu(Ⅱ)charge transfer bands centred on trinuclear molecules(2–4)and their absence for the ionic sample 1 without CN^(-)-bridges.Additionally,detailed descriptions of the energy level diagrams of 1–4 with the frontier molecular orbitals and possible optical transitions were made.Magnetic studies indicated paramagnetic behaviour with weak antiferromagnetic interactions at low temperature.Finally,photomagnetic studies of 1–3 showed the increase of magnetization after irradiation with 473 and 410 nm light at 10 K.Comparative analysis of all data suggests that the photomagnetic effect in 1 is well described by the lightinduced excited spin-state trapping(LIESST)effect in the Mo(Ⅳ)centre,while other cyanido-bridged compounds prefer the metal-to-metal charge transfer with minor contribution of LIESST effects.展开更多
Light-induced transformation from diamagnetic ligand to paramagnetic radical offers a unique approach to modulating the magnetization dynamics of magnetic compounds.In this study,we present a two-dimensional Yb(III)co...Light-induced transformation from diamagnetic ligand to paramagnetic radical offers a unique approach to modulating the magnetization dynamics of magnetic compounds.In this study,we present a two-dimensional Yb(III)coordination polymer 1 and its Y(III)-diluted analog 1@Y,along with their lightinduced radical forms,1a and 1a@Y.Due to the presence of light-induced radicals,the magnetic susceptibility properties(_(χM)T values)of 1a and 1a@Y featured remarkable 82.3%and 88.9%enhancements,respectively,at room temperature,compared with those of 1 and 1@Y,and were accompanied by an unexpected increase in the effective energy barrier for magnetization dynamics.The magnetization dynamics of 1 and 1a involved both Orbach and Raman processes,while 1@Y and 1a@Y exhibited two Raman processes,indicating that the Orbach process that occurred in 1 and 1a was mainly attributed to the magnetic coupling between Yb(III)ions.This work showcases the potential of light-induced radical transformation for tuning both the static and dynamic magnetic properties of lanthanide coordination polymers.展开更多
Crystalline complexes that exhibited light switchable proton conductivity are of great interest but still a challenge in material science.Herein,a terbium phosphonate chain complex was synthesized through assembly of ...Crystalline complexes that exhibited light switchable proton conductivity are of great interest but still a challenge in material science.Herein,a terbium phosphonate chain complex was synthesized through assembly of electron-rich phosphonate units,electron-deficient polypyridine components and paramagnetic Tb^(3+)ions.Via light irradiation and heat treatment,the photogenerated radicals could simultaneously and reversibly tune the photochromic,luminescent and magnetic properties.Originating from the abundant hydrogen bonding networks formed between PO_3 groups and lattice water molecules,proton conductive behaviour was explored with high proton conductivity of(1.74±0.19)×10^(-3)S cm^(-1)at 80°C and 100%relative humidity.Importantly,accompanied with the colorless sample changed to blue,the proton conductivity increased about 20%after room temperature light illumination,implying that light irradiation could act as an external stimulus to enhance the conductive properties of original material.This work innovatively realized the light responsive conductive property in the electron transfer photochromic materials,providing a novel strategy for the construction of smart materials.展开更多
Herein,we report the first example showing the reversible on-off switching of spin-crossover(SCO)property by solid state photochemical[2+2]reaction.The ultraviolet(UV)light-induced[2+2]cycloaddition reaction of 3-spy ...Herein,we report the first example showing the reversible on-off switching of spin-crossover(SCO)property by solid state photochemical[2+2]reaction.The ultraviolet(UV)light-induced[2+2]cycloaddition reaction of 3-spy ligands in a twodimensional(2D)Hofmann-type framework[Fe(3-spy)_(2){Pd(CN)_(4)}](1,3-spy=3-styrylpyridine),which shows a hysteretic twostep SCO behavior,gives a 3D Hofmann-type framework[Fe(rctt-3-ppcb){Pd(CN)_(4)}](2,rctt-3-ppcb=rctt-1,3-bis(3-pyridyl)-2,4-bis(phenyl)cyclobutane,r=reference group,c=cis and t=trans)accompanied with the disappearing of SCO properties.Moreover,upon heating at 250℃ for 12 h,the rctt-3-ppcb ligand in 2 could be partially dedimerized to 3-spy with 68%completion through single-crystal-to-single-crystal(SCSC)transformation,giving the annealing complexes[Fe(3-spy)1.36(rctt-3-ppcb)0.32{Pd(CN)_(4)}](3)which display an incomplete SCO behavior.The 2■3 interconversion is successfully achieved via continuous UV irradiation and thermal annealing,demonstrating the effectiveness of photochemical[2+2]reaction on switching on-off SCO properties.展开更多
Postsynthesis of the paramagnetic square-shaped complex{[(Tp*Me)Fe(μ-CN)_(2)(CN)][Co(dmbpy)_(2)]}_(2)(BPh_(4))_(2)·6MeCN·H2O[1,Tp*Me=tris(3,4,5-trimethylpyrazole)-borate;dmbpy=4,4′-dimethyl-2,2′-bipyridin...Postsynthesis of the paramagnetic square-shaped complex{[(Tp*Me)Fe(μ-CN)_(2)(CN)][Co(dmbpy)_(2)]}_(2)(BPh_(4))_(2)·6MeCN·H2O[1,Tp*Me=tris(3,4,5-trimethylpyrazole)-borate;dmbpy=4,4′-dimethyl-2,2′-bipyridine)]by grafting transition metal(II)thiocyanates via its terminal cyano groups afforded three hexanuclear[Fe_(2)Co_(2)M_(2)]clusters(M=Zn,2;Co,3;Cd,4).The peripheral metal-complex units serving as excellent electron acceptors were found to help stabilize the low-temperature state of Fe^(II,LS)–Co^(III,LS) within the complex core.展开更多
基金Project supported by the National Natural Science Foundation of China(21971123,21931004,92156002)。
文摘The magnetization dynamics of lanthanide coordination compounds are fundamentals governing their potential applications such as information storage or molecular switches.Herein,two two-dimensional coordination polymers[Er(CA)_(1.5)(bpy)(DMF)]_(n)(1)and[Er(CA)_(1.5)(phen)(DMF)]_(n)(2)(H_(2)CA=2,5-dichloro-3,6-dihydroxy-p-quinone,bpy=2,2'-bipyridine,phen=1,10-phenanthroline)were synthesized and fully characterized.By the irradiation of ultraviolet light,1 and 2 were converted to la and 2a which contain light-generated radicals,inducing an increase ofχ_(MT)at room temperature.A detailed study of the dynamic magnetic property shows that the magnetization dynamics observed for 1 and la are dominated by Raman process,but Orbach and Raman processes are observed in 2 and 2a.The structural factors influencing the magnetic properties of this photomagnetic system are discussed.
基金supported by the National Natural Science Foundation of China (22102064 and 22472069)the Postgraduate Research&Practice Innovation Program of Jiangsu Province (KYCX24_3947)。
文摘The urgent imperative for carbon-neutral chemical production has accelerated the development of solardriven catalytic technologies that convert abundant C_(1) feedstocks(CO_(2) and CH_(4))into value-added C_(2+)molecules.Standalone photocatalysis remains constrained by rapid chargecarrier recombination and poor C-C coupling selectivity.This review critically examines multi-field-coupled catalysis-a transformative paradigm synergistically integrating solar energy with auxiliary thermal,electric,and magnetic fields.Through mechanistic dissection of photothermal,photoelectrochemical,and photomagnetic field cooperativities,it is summarized that thermal gradients attenuate phonon scattering to enhance charge-carrier drift mobility while vibrationally stabilizing reactive intermediates,electric potentials drive vectorial charge transport via Coulomb-forcedirected separation and band alignment,and magnetic fields modulate spin-selective electron transfer through Zeeman splitting-mediated polarization to boost reaction specificity.This synergistic multi-field integration circumvents intrinsic limitations of single-mode photocatalysis by collectively reconfiguring reaction coordinates for selective C-C coupling.We further address persistent challenges in resolving ultrafast interfacial charge-transfer dynamics,scaling integrated field reactors for industrial deployment,and advancing in situ operando characterization of multiscale processes.Strategic research priorities are proposed to advance sustainable multifield-coupled catalytic production of fuels and platform chemicals.
基金supported in part by a Grant-in-Aid for Scientific Research(A)from JSPS KAKENHI(Grant Number 20H00369)Advanced Technologies for Carbon-Neutral(ALCA)-Next from JST(JPMJAN23A2)+2 种基金CNRS-University of Tokyo“Excellence Science”Joint Research Program,Second CNRS–University of Tokyo PhD Joint Program.The Cryogenic Research Center,The University of Tokyo,the Center for Nano Lithography&Analysis,The University of Tokyo,Quantum Leap Flagship Program(Q-LEAP,Grant Number JPMXS0118068681)by MEXT is also acknowledged for supportKazuki Nakamura was supported by the World-Leading Innovative Graduate Study Program for Materials Research,Information,and Technology(MERIT-WINGS)the Fellowship for Integrated Materials Science and Career Development.Koji Nakabayashi acknowledges the Iketani Science and Technology Foundation(Grant Number 0351111-A).
文摘A newly synthesized photomagnet based on a cyanido-bridged Co-W assembly,[{Co(isoquinoline)_(4)}_(3){W(CN)_(8)}_(2)]·_(2)EtOH(CoWisoq),exhibits a controllable photoinduced(PI)phase with a metamagnetic behavior.The PI phase shows a transition from paramagnetic to ferromagnetic with a coercive field of 550 Oe at 2 K.It has a monoclinic(P21/n)crystal structure and is comprised of two-dimensional cyanido-bridged Co-W coordination layers with two crystallographically independent Co sites(Co1,Co2)and one W site.Both Co sites adopt a pseudo-octahedral six-coordinated geometry involving four isoquinoline and two cyanide ligands.π-πinteractions are induced at half of the isoquinoline ligands in Co1 and all of those in Co2 sites,suggesting that the coordination environment at the Co1 site has structural flexibility.CoWisoq displays a thermal phase transition around 140 K with a small thermal hysteresis due to the charge transfer-induced spin transition between Co^(Ⅱ)-W^(Ⅴ) of the high temperature(HT)phase and Co ^(Ⅲ)-W^(Ⅳ) of the low temperature(LT)phase.This charge transfer,which is also responsible for a drastic color change between purple(HT)and yellow(LT),involves only the structurally flexible Co1 sites.The ligand field,which is composed of four isoquinoline and two cyanide ligands,contributes to a unique metal-to-metal charge transfer absorption band of the LT phase at 1025 nm.Irradiation of the LT phase with near-infrared light produces a PI phase with the CoII-WV state.
基金supported by the National Key Research and Development Program of China(2018YFA0306001)the NSFC(22075323)the Pearl River Talent Plan of Guangdong(2017BT01C161).
文摘The pursuit of spin crossover(SCO)materials with photoswitchable multistability is driven by fascinating perspectives toward light-response switches and opto-magnetic memory devices.Herein,we report a 3D Hofmann-type metal–organic framework[Fe(bpn){Ag(CN)_(2)}_(2)]·1.5(Fnaph)(bpn=1,4-di(pyridin-4-yl)naphthalene,Fnaph=1-fluoronaphthalene),which displays an incomplete two-step SCO behaviour.The asymmetric host–vip interactions induce an intermediate HS–LS state at low temperature.Photomagnetic measurements exhibited an extremely rare bidirectional light-induced excited spin-state trapping(LIESST)effect with green and near-IR light irradiation,in which both metastable HS*and hidden LS*states were revealed at 10 K.The light-induced tristability paves the way for designing optomagnetic memory devices.
基金supported in part by a JSPS Grant-in-Aid for Scientific Research(A)(Grant Number JP20H00369)a Grantin-Aid for Scientific Research on Innovative Area Soft Crystals(Area No.2903,JP17H06367)+4 种基金Grant-in-Aid for Specially Promoted Research(Grant Number JP15H05697)IM–LED LIA(CNRS)and CNRS-University of Tokyo“Excellence Science”Joint Research ProgramWe also acknowledge the Cryogenic Research Center,The University of Tokyo,the Center for Nano Lithography&Analysis,The University of Tokyo supported by MEXT,and the MEXT Quantum Leap Flagship Program(Grant Number JPMXS0118068681)for supportK.K.is grateful for a Grant in-Aid for JSPS fellows(Grant Number JP20J20245)O.S.is grateful for JSPS KAKENHI Grant Number JP21K14582.
文摘The crystal engineering of octacyanidomolybdate(Ⅳ)ions and copper(Ⅱ)complexes with two types of chelating ligands:multidentate blocking ligand,tren=(tris(2 aminoethyl)amine),and bidentate ligand capable of forming unusual organic bridges,tn=1,3-diaminopropane,resulted in the formation of{[Cu(tren)]2(μ-tn)}·[Mo(CN)8]·7.5H2O(1)and{[Cu(tren)]2(μ-tn)}·[Mo(CN)8]·{[Cu(tren)]2[Mo(CN)8]}·9H2O(2).The crystal structure of 1 comprises isolated anions[Mo(CN)8]4-wrapped with charge-compensating units{[Cu(tren)]2(μ-tn)}^(4+)stabilised by extensive H-bond networks.Compound 2 forms alternating layers consisting of the same ions as 1 and neutral cyanido-bridged V-shaped trinuclear molecules{[Cu(tren)]2[Mo(CN)8]}.Additionally,two previously reported V-shaped trinuclear reference systems were synthesised:[Cu(tn)2]2[Mo(CN)_(8)]·2H_(2)O(3)and[Cu(tren)]2[Mo(CN)8]·5.25H2O(4).UV–Vis–NIR absorption spectroscopy,supported by quantum chemical calculations(DFT and TD-DFT),confirmed the presence of Mo(Ⅳ)to Cu(Ⅱ)charge transfer bands centred on trinuclear molecules(2–4)and their absence for the ionic sample 1 without CN^(-)-bridges.Additionally,detailed descriptions of the energy level diagrams of 1–4 with the frontier molecular orbitals and possible optical transitions were made.Magnetic studies indicated paramagnetic behaviour with weak antiferromagnetic interactions at low temperature.Finally,photomagnetic studies of 1–3 showed the increase of magnetization after irradiation with 473 and 410 nm light at 10 K.Comparative analysis of all data suggests that the photomagnetic effect in 1 is well described by the lightinduced excited spin-state trapping(LIESST)effect in the Mo(Ⅳ)centre,while other cyanido-bridged compounds prefer the metal-to-metal charge transfer with minor contribution of LIESST effects.
基金supported by the National Natural Science Foundation of China(grant nos.22435002a,92156002,21971123,and 62401563)L.U.acknowledges the financial support of the research projects A-800079-00-00,A-8000017-00-00,and A-8001894-00-00 of the National University of Singapore(NUS)+1 种基金Ab initio calculations were done on the Advanced Supercomputer for Petascale Innovation,Research and Enterprise 2A(ASPIRE-2A)cluster of the Singapore National Supercomputing Centre(NSCCwww.nscc.sg)under project 11001278.The highperformance computational(HPC)resources of NUS(HPC-NUS)are gratefully acknowledged.The NUS Research Scholarship program supported W.H.
文摘Light-induced transformation from diamagnetic ligand to paramagnetic radical offers a unique approach to modulating the magnetization dynamics of magnetic compounds.In this study,we present a two-dimensional Yb(III)coordination polymer 1 and its Y(III)-diluted analog 1@Y,along with their lightinduced radical forms,1a and 1a@Y.Due to the presence of light-induced radicals,the magnetic susceptibility properties(_(χM)T values)of 1a and 1a@Y featured remarkable 82.3%and 88.9%enhancements,respectively,at room temperature,compared with those of 1 and 1@Y,and were accompanied by an unexpected increase in the effective energy barrier for magnetization dynamics.The magnetization dynamics of 1 and 1a involved both Orbach and Raman processes,while 1@Y and 1a@Y exhibited two Raman processes,indicating that the Orbach process that occurred in 1 and 1a was mainly attributed to the magnetic coupling between Yb(III)ions.This work showcases the potential of light-induced radical transformation for tuning both the static and dynamic magnetic properties of lanthanide coordination polymers.
基金supported by the National Natural Science Foundation of China(21901133,22071125,22071126,21571111)Key Research and Development Project of Shandong Province(2019GGX102006)。
文摘Crystalline complexes that exhibited light switchable proton conductivity are of great interest but still a challenge in material science.Herein,a terbium phosphonate chain complex was synthesized through assembly of electron-rich phosphonate units,electron-deficient polypyridine components and paramagnetic Tb^(3+)ions.Via light irradiation and heat treatment,the photogenerated radicals could simultaneously and reversibly tune the photochromic,luminescent and magnetic properties.Originating from the abundant hydrogen bonding networks formed between PO_3 groups and lattice water molecules,proton conductive behaviour was explored with high proton conductivity of(1.74±0.19)×10^(-3)S cm^(-1)at 80°C and 100%relative humidity.Importantly,accompanied with the colorless sample changed to blue,the proton conductivity increased about 20%after room temperature light illumination,implying that light irradiation could act as an external stimulus to enhance the conductive properties of original material.This work innovatively realized the light responsive conductive property in the electron transfer photochromic materials,providing a novel strategy for the construction of smart materials.
基金supported by the National Key Research and Development Program of China(2018YFA0306001)the Nas tional Natural Sciences Foundation of China(21773316,21801258,21821003)the Pearl River Talent Plan of Guangdong(2017BT01C161)。
文摘Herein,we report the first example showing the reversible on-off switching of spin-crossover(SCO)property by solid state photochemical[2+2]reaction.The ultraviolet(UV)light-induced[2+2]cycloaddition reaction of 3-spy ligands in a twodimensional(2D)Hofmann-type framework[Fe(3-spy)_(2){Pd(CN)_(4)}](1,3-spy=3-styrylpyridine),which shows a hysteretic twostep SCO behavior,gives a 3D Hofmann-type framework[Fe(rctt-3-ppcb){Pd(CN)_(4)}](2,rctt-3-ppcb=rctt-1,3-bis(3-pyridyl)-2,4-bis(phenyl)cyclobutane,r=reference group,c=cis and t=trans)accompanied with the disappearing of SCO properties.Moreover,upon heating at 250℃ for 12 h,the rctt-3-ppcb ligand in 2 could be partially dedimerized to 3-spy with 68%completion through single-crystal-to-single-crystal(SCSC)transformation,giving the annealing complexes[Fe(3-spy)1.36(rctt-3-ppcb)0.32{Pd(CN)_(4)}](3)which display an incomplete SCO behavior.The 2■3 interconversion is successfully achieved via continuous UV irradiation and thermal annealing,demonstrating the effectiveness of photochemical[2+2]reaction on switching on-off SCO properties.
基金supported by the National Natural Science Foundation of China(nos.21671095 and 21901108)and startup funds from SUSTech.
文摘Postsynthesis of the paramagnetic square-shaped complex{[(Tp*Me)Fe(μ-CN)_(2)(CN)][Co(dmbpy)_(2)]}_(2)(BPh_(4))_(2)·6MeCN·H2O[1,Tp*Me=tris(3,4,5-trimethylpyrazole)-borate;dmbpy=4,4′-dimethyl-2,2′-bipyridine)]by grafting transition metal(II)thiocyanates via its terminal cyano groups afforded three hexanuclear[Fe_(2)Co_(2)M_(2)]clusters(M=Zn,2;Co,3;Cd,4).The peripheral metal-complex units serving as excellent electron acceptors were found to help stabilize the low-temperature state of Fe^(II,LS)–Co^(III,LS) within the complex core.
