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Updated: Jun 5, 2026
Electric-field Control of Electronic States in WS2 Nanodevices by Electrolyte Gating
Published on: April 12, 2018
Achieving Ambient-Temperature Multiway Bistability via Electron-Transfer-Coupled Spin-State Switching in 2D Hexagonal
Krishna Kaushik1, Sakshi Mehta1, Sujit Kamilya1
1Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore, India.
None:
Magnetic materials exhibiting bistability under ambient conditions are highly attractive for applications in data-storage, memory devices, sensors, and stimuli-responsive technologies. Cyanide-bridged octacyanometallates provide a uniquely versatile platform for constructing molecular architectures with tunable electronic and magnetic properties. Here, we present two structurally related cyanide-bridged 2D hexagonal [W─Co] networks that combine structural adaptability with multifunctional switching. Complex 1 {[W(CN)8]2[Co(V-im)4]3}n, undergoes a rare single-crystal-to-single-crystal (SC-SC) transformation to yield complex 2 {[W(CN)8]2[Co(V-im)4]2[Co(V-im)2(DMF)2].4H2O}n, enabling a direct structure-property correlation within the same material system. Complex 1 displays a reversible, single-step, thermally induced metal-to-metal electron transfer (MMET), while complex 2 exhibits a two-step MMET process operating near ambient temperature. Both complexes further demonstrate light-induced bistability: near-infrared irradiation (808, 900 nm) drives conversion of the diamagnetic {WIV LS-CN-CoIII LS} ground state to a metastable paramagnetic {WV LS-CN-CoII HS} state, which is reversibly switched OFF by visible-light irradiation (405, 635 nm). The bistability is unambiguously established by combining variable-temperature magnetic susceptibility, photomagnetic measurements, and synchrotron x-ray absorption spectroscopy, which directly probes the local electronic reorganization at W and Co centers. This work demonstrates how molecular engineering of cyanide-bridged 2D frameworks can deliver robust, multi-stimuli-responsive bistable materials that operate close to room temperature, offering a promising platform for molecular spintronics and optoelectronic devices.
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