Reversible Electron Transfer in a Linear {Fe₂Co} Trinuclear Complex Induced by Thermal Treatment and Photoirraditaion

Light‐Induced Bidirectional Metal‐to‐Metal Charge Transfer in a Linear Fe2Co Complex

“…At 296 K, the Co À N cyanide and Co À N Bpi bond lengths were measured as 2.093(4) and 2.120(4)-2.134(4) ,and the Fe À C and FeÀNbond lengths were 1.886(4)-1.925(5) and 1.965(4)-1.982(4) ,r espectively.S uch structural parameters are consistent with compounds containing {Fe III LS ÀCNÀCo II HS } linkages, [8] indicating that HS Co II and LS Fe III ions were present according to charge compensation. Upon cooling the crystals to 90 K, the Co À N cyanide and Co À N Bpi bond lengths abruptly decreased to 1.872(5) and 1.932(5)-1.954 (5) ,being consistent with that observed for Co III LS .…”

“…It was found that faster scan rates achieved larger thermal hysteresis (Figure S7 b), as reported for other FeCo systems. [8,16] However,t he absorbance of the LMCT/MLCT band at 429 nm decreased, which was associated with the disappearance of the Co II !Fe III IVCT band at 587 nm. At 298 K, one broad absorption band was observed at 429 nm, assigned to ligandto-metal charge transfer (LMCT) and/or MLCT in the Fe and Co chromophores.Bycomparison, asmall shoulder at 587 nm could be attributed to Co II !Fe III intervalence charge transfer (IVCT).…”

“…[5] Moreover,the light-induced process is on the pico-or femtosecond scale, [6] thus providing afast response to functional signals.I ndeed, bidirectional switching of molecular materials using light irradiation has become ah ot topic due to its rich applications in future molecular electronic switches,actuators,and sensors. [8] However, photomagnetic switching properties were experimentally studied and electric polarity switching was deduced from the asymmetric geometry change of charges induced by the electron transfer in the molecular trinuclear entity.I ti sc hallenging to realize bidirectional switching using alternating frequencies of light irradiation with light of different wavelengths,a nd studying both the dielectric and magnetic properties of the two states is also aw orthy challenge. [8] However, photomagnetic switching properties were experimentally studied and electric polarity switching was deduced from the asymmetric geometry change of charges induced by the electron transfer in the molecular trinuclear entity.I ti sc hallenging to realize bidirectional switching using alternating frequencies of light irradiation with light of different wavelengths,a nd studying both the dielectric and magnetic properties of the two states is also aw orthy challenge.…”

Three Properties in One Coordination Complex: Chirality, Spin Crossover, and Dielectric Switching

“…Photoexcitation measurements on 1R (Figure ) and 1S (Figure S5) indicate the occurrence of the LIESST (light‐induced excited spin‐state trapping) effect . The samples were cooled to 10 K and were irradiated with a 532 nm laser ( P = 30 mW cm –2 ) for 1.5 h. After reaching photoexcited magnetic saturation, the laser was switched off.…”

Probing the Local Magnetic Structure of the [FeIII(Tp)(CN)3]− Building Block Via Solid‐State NMR Spectroscopy, Polarized Neutron Diffraction, and First‐Principle Calculations

“…One of the reasonsf or this is the ability of the cyanido bridging ligand to efficiently promote electronic communication (or electron transfer) between different metal ions. [9][10][11][12][13] Af ew years ago, we undertook af undamental study of the [Fe III (Tp)(CN) 3 ] À building block with the aim of gaining a deeper understanding of its properties by probing the magnetism at the local level. [5,6] In the early 2000s, some of us synthesized various [Fe(L)(CN) x ] À building blocks (L = polydentate ligands, x = 3o r 4) allowing the preparation of low-dimensional magnetic systems.…”