Molecular materials are playing a pivotal role in the advancement of prospective THz technologies.Herein,we have prepared nine isostructural coordination complexes of general formula[Ln^(Ⅲ)(H_(2)O)_(3)][AgI(CN)_(2)]_...Molecular materials are playing a pivotal role in the advancement of prospective THz technologies.Herein,we have prepared nine isostructural coordination complexes of general formula[Ln^(Ⅲ)(H_(2)O)_(3)][AgI(CN)_(2)]_(3)(LnAg,Ln=La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,and Dy).Vibrational spectroscopy has unveiled gradual changes in theν(CuN)stretching frequencies within both infrared(IR)and Raman spectra from LaAg to DyAg,stemming from incremental alterations in crystallographic unit cell parameters and volumes.Similarly,the THz spectra manifest pronounced absorption signals between 1.0 to 1.2 THz,which can be judiciously tuned by varying lanthanide(^(Ⅲ))ion and measurement temperature.Ab initio density-functional theory(DFT)calculations of THz spectra elucidate the primary contribution from opposite translational vibrations of Ag atoms and O atoms from H_(2)O around Ln(^(Ⅲ))atoms.Furthermore,thin films of LnAg can achieve a large return loss in a broad bandwidth in impedance-matching simulations.展开更多
We report the synthesis and characterization of two symmetric homo-dimetallic lanthanide complexes based on methyl-substituted 8-hydroxyquinoline(HMeQ).The aryloxo-bridged core gives rise to weak magnetic coupling bet...We report the synthesis and characterization of two symmetric homo-dimetallic lanthanide complexes based on methyl-substituted 8-hydroxyquinoline(HMeQ).The aryloxo-bridged core gives rise to weak magnetic coupling between pairs of ErⅢand YbⅢions,as revealed by magnetic and EPR spectroscopy studies.EPR measurements of magnetically dilute species,coupled with CASSCF-SO calculations,allows modelling of the EPR spectra of the exchange coupled species and the magnetic data simultaneously.This work adds to the database of exchange coupled{Ln}_(2)molecules which have been thoroughly characterised by EPR spectroscopy and modelled using an S_(eff)=1/2 approach to describe the interaction of ground Kramers states,and highlights the differences between centro-symmetric and asymmetric dimetallics.展开更多
The synthesis of three new tetranuclear heterometallic Co^(Ⅲ)–Dy^(Ⅲ)planar butterfly coordination complexes is reported of molecular formulae[Dy_(2)^(Ⅲ)Co_(2)^(Ⅲ)(OH)_(2)(teaH)_(2)(acac)_(6)]·MeCN(3),[Dy_(2...The synthesis of three new tetranuclear heterometallic Co^(Ⅲ)–Dy^(Ⅲ)planar butterfly coordination complexes is reported of molecular formulae[Dy_(2)^(Ⅲ)Co_(2)^(Ⅲ)(OH)_(2)(teaH)_(2)(acac)_(6)]·MeCN(3),[Dy_(2)^(Ⅲ)Co_(2)^(Ⅲ)(OH)_(2)(bdea)_(2)(acac)_(6)]·2H_(2)O(4)and[Dy_(2)^(Ⅲ)Co_(2)^(Ⅲ)(OH)_(2)(edea)_(2)(acac)_(6)]·2H_(2)O·4MeCN(5)(teaH_(3)=triethanolamine,bdeaH_(2)=N-n-butyldiethanolamine,edeaH_(2)=N-ethyldiethanolamine and acacH=acetylacetone)each of which display singlemolecule magnet(SMM)behaviour.Importantly these new compounds are related to several{Co_(2)^(Ⅲ)Dy_(2)^(Ⅲ)}SMM compounds allowing for the study of the effect that the subtle changes in structure have on the SMM properties.Ab initio calculations are performed on 3–5,as well as on the related structural derivatives in order to gain insight on the effect the structural changes have on the dynamic magnetic behaviour.展开更多
We report a trinuclear dysprosium single-molecule magnet,[Dy_(3)(μ_(3)-CO_(3))(Clbbpen)_(3)](CF_(3)SO_(3))·6MeCN,which has a perfectly equilateral triangular structure.The Ising-like anisotropy of each Dy(III)si...We report a trinuclear dysprosium single-molecule magnet,[Dy_(3)(μ_(3)-CO_(3))(Clbbpen)_(3)](CF_(3)SO_(3))·6MeCN,which has a perfectly equilateral triangular structure.The Ising-like anisotropy of each Dy(III)site is oriented almost normal to the triangular plane,and magnetic dipole interactions between the spins cause an antiparallel Ising ground state.Crossing of the antiferromagnetic states by the ferromagnetic state occurs at ca.0.2 T and gives rise to a characteristic step in magnetic hysteresis loops.This molecule thus serves as a perfectly triangular model system to explore frustrated Ising anisotropy.展开更多
基金financed in part by a JSPS Grant-in-Aid for Scientific Research(A)(Grant Number 20H00369),IRL DYNACOM(CNRS),the CNRS-University of Tokyo“Excellence Science”Joint Research Program,and the Second CNRS-University of Tokyo PhD Joint ProgramThe authors 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 the support.G.L.is grateful to JSPS KAKENHI(Grant Number 23KJ0736)+4 种基金O.S.is thankful to JSPS KAKENHI(Grant Number 21K14582)K.K.acknowledges a Grant-in-Aid for JSPS fellows(Grant Number 23K19238)Y.M.and L.W.thank the JST SPRING(Grant Number JPMJSP2108)K.N.recognizes the Iketani Science and Technology Foundation(Grant Number 0351111-A)M.Y.is grateful to JSPS Grant-in-Aid for Young Scientists(Grant Number JP24K17606)。
文摘Molecular materials are playing a pivotal role in the advancement of prospective THz technologies.Herein,we have prepared nine isostructural coordination complexes of general formula[Ln^(Ⅲ)(H_(2)O)_(3)][AgI(CN)_(2)]_(3)(LnAg,Ln=La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,and Dy).Vibrational spectroscopy has unveiled gradual changes in theν(CuN)stretching frequencies within both infrared(IR)and Raman spectra from LaAg to DyAg,stemming from incremental alterations in crystallographic unit cell parameters and volumes.Similarly,the THz spectra manifest pronounced absorption signals between 1.0 to 1.2 THz,which can be judiciously tuned by varying lanthanide(^(Ⅲ))ion and measurement temperature.Ab initio density-functional theory(DFT)calculations of THz spectra elucidate the primary contribution from opposite translational vibrations of Ag atoms and O atoms from H_(2)O around Ln(^(Ⅲ))atoms.Furthermore,thin films of LnAg can achieve a large return loss in a broad bandwidth in impedance-matching simulations.
基金The University of Manchester and EPSRC EPR National Research Facility(NS/A000055/1)the EPR spectrometers and SQUID magnetometer,and the EPSRC for funding an X-ray diffractometer(grant number EP/K039547/1).+3 种基金The University of Manchester for a Presidential Fellowship,The Royal Society for a University Research Fellowship,and the European Research Council for a Starting Grant(ERC-2019-STG-851504)R.E.P.W.thanks the EPSRC for an Established Career Fellowship(EP/R011079/1)the European Research Council for an Advanced Grant(ERC-2017-ADG-786734)the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation programme(grant agreements no.786734 and 851504).
文摘We report the synthesis and characterization of two symmetric homo-dimetallic lanthanide complexes based on methyl-substituted 8-hydroxyquinoline(HMeQ).The aryloxo-bridged core gives rise to weak magnetic coupling between pairs of ErⅢand YbⅢions,as revealed by magnetic and EPR spectroscopy studies.EPR measurements of magnetically dilute species,coupled with CASSCF-SO calculations,allows modelling of the EPR spectra of the exchange coupled species and the magnetic data simultaneously.This work adds to the database of exchange coupled{Ln}_(2)molecules which have been thoroughly characterised by EPR spectroscopy and modelled using an S_(eff)=1/2 approach to describe the interaction of ground Kramers states,and highlights the differences between centro-symmetric and asymmetric dimetallics.
文摘The synthesis of three new tetranuclear heterometallic Co^(Ⅲ)–Dy^(Ⅲ)planar butterfly coordination complexes is reported of molecular formulae[Dy_(2)^(Ⅲ)Co_(2)^(Ⅲ)(OH)_(2)(teaH)_(2)(acac)_(6)]·MeCN(3),[Dy_(2)^(Ⅲ)Co_(2)^(Ⅲ)(OH)_(2)(bdea)_(2)(acac)_(6)]·2H_(2)O(4)and[Dy_(2)^(Ⅲ)Co_(2)^(Ⅲ)(OH)_(2)(edea)_(2)(acac)_(6)]·2H_(2)O·4MeCN(5)(teaH_(3)=triethanolamine,bdeaH_(2)=N-n-butyldiethanolamine,edeaH_(2)=N-ethyldiethanolamine and acacH=acetylacetone)each of which display singlemolecule magnet(SMM)behaviour.Importantly these new compounds are related to several{Co_(2)^(Ⅲ)Dy_(2)^(Ⅲ)}SMM compounds allowing for the study of the effect that the subtle changes in structure have on the SMM properties.Ab initio calculations are performed on 3–5,as well as on the related structural derivatives in order to gain insight on the effect the structural changes have on the dynamic magnetic behaviour.
基金supported by the National Key Research and Development Program of China(2018YFA0306001)the NSFC(Grant No.,21620102002,21771200,21822508,21821003)+2 种基金the Pearl River Talent Plan of Guangdong(2017BT01C161)The Royal Society for a University Research FellowshipThe University of Manchester for a President’s Doctoral Scholarship award.
文摘We report a trinuclear dysprosium single-molecule magnet,[Dy_(3)(μ_(3)-CO_(3))(Clbbpen)_(3)](CF_(3)SO_(3))·6MeCN,which has a perfectly equilateral triangular structure.The Ising-like anisotropy of each Dy(III)site is oriented almost normal to the triangular plane,and magnetic dipole interactions between the spins cause an antiparallel Ising ground state.Crossing of the antiferromagnetic states by the ferromagnetic state occurs at ca.0.2 T and gives rise to a characteristic step in magnetic hysteresis loops.This molecule thus serves as a perfectly triangular model system to explore frustrated Ising anisotropy.
