Light-induced hidden multistability in a spin crossover metal–organic framework

Abstract

The pursuit of spin crossover (SCO) materials with photo-switchable multistability is driven by the fascinating perspectives toward light-response switches and opto-magnetic memory devices. Herein, we report a 3D Hofmann-type metal...

Pressure-Induced Hysteretic and Abrupt Spin Transition in Amine Functionalized Isoquinoline-Based Two-Dimensional FeII Hofmann Frameworks

“…To tune SCO profiles, pyridine-, pyrazine-, and triazole-based − ligands have been used extensively, but recently the fused bicyclic azine-based ligand came into the picture in SCO-based materials. , Till now there are only two reports where the isoquinoline-based ligand is used in a 2D Hofmann clathrate [Fe­(isoq) 2 {Ag­(CN) 2 } 2 ] which exhibits a light induced excited spin state trapping (LIESST) effect and tristability for its spin states over a large temperature range, containing three inequivalent Fe II sites, with the sequence of γ HS = 1 ↔ γ HS = 3/4 ↔ γ HS = 1/4 . Similarly, Real and co-workers have used the same ligand with square planar M­(CN) 4 2– (M = Pt and Pd) to achieve SCO behavior.…”

Bidirectional photoswitchability in an iron(III) spin crossover complex: Symmetry-breaking and solvent effects

“…Moreover, light irradiation sometimes allows access to hidden spin states that are not accessible thermally (Figure 1b). While common in coordination polymers, [40][41][42][43][44][45] we are aware of only one mononuclear complex were this has been observed. 36 where the different alcohols result in symmetry-breaking SCO or non-symmetry breaking and gradual SCO, respectively.…”

Guest-triggered “Soma–Iwamoto-type” penetration complex {Fe(4-methoxypyrimidine)2[M(CN)2]2}·Guest (M = Ag, Au)

“…The first type is bridged by square planar tetra-coordinated divalent cyanometalate [M(CN) 4 ] 2− (M = Ni, Pd, Pt) 3–10 such as Fe(pz)[M(CN) 4 ]·H 2 O (M = Ni, Pd, Pt), 10 while the other is bridged by linear coordinated monovalent cyanometalate [M(CN) 2 ] − (M = Ag, Au). 11–16 The first complex possessing the latter type of structure is [Cd(4,4′-bpy) 2 {Ag(CN) 2 } 2 ], 17 while the second is [Cd(py) 2 {Ag(CN) 2 } 2 ], 18,19 which were both reported by Soma and Iwamoto, and therefore, the latter type of structures are denoted as “Soma–Iwamoto types”. Coordination polymer frameworks of Hofmann-type ML 2 M′(CN) 4 (M′ = Ni, Pd, Pt) structures are different from that of the Soma–Iwamoto type ML 2 [M′′(CN) 2 ] 2 (M′′ = Ag, Au).…”