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
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(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.