Unravelling of a [High Spin – Low Spin] ↔ [Low Spin – High Spin] Equilibrium in Spin-Crossover Iron(II) Dinuclear Helicates Using Paramagnetic NMR Spectroscopy

Aleshin D. Y.; Diego R.; Barrios L.; Nelyubina Y. V.; Aromi G.; Novikov V.V.

doi:10.1002/anie.202110310

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Unravelling of a [High Spin – Low Spin] ↔ [Low Spin – High Spin] Equilibrium in Spin-Crossover Iron(II) Dinuclear Helicates Using Paramagnetic NMR Spectroscopy

Angewandte Chemie - International Edition. 2022. Vol. 61. Article 202110310.

Aleshin D. Y., Diego R., Barrios L., Nelyubina Y. V., Aromi G., Novikov V.V.

Spin-crossover between high-spin (HS) and low- spin (LS) states of selected transition metal ions in polynuclear and polymeric compounds is behind their use as multistep switchable materials in breakthrough electronic and spintronic devices. We report the first successful attempt to observe the dynamics of a rarely found broken-symmetry spin state in binuclear complexes, which mixes the states [HS-LS] and [LS- HS] on a millisecond timescale. The slow exchange between these two states, which was identified by paramagnetic NMR spectroscopy in solutions of two spin-crossover iron(II) binuclear helicates that are amenable to molecular design, opens a path to double quantum dot cellular automata for information storage and processing.

Research target: Chemistry

Language: English

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Keywords: spin-crossover molecular compounds broken symmetry helicates paramagnetic NMR

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A self-consistent statistical-mechanical theory of the Hall effect in electrolyte solutions is developed by extending the self-consistent Debye–Hückel–Onsager (SCDHO) framework to crossed electric and magnetic fields. The theory incorporates non-local ionic charge distributions via Slater-type form factors, regularizing the Coulomb interaction at short range, and accounts for dielectric friction through ion-specific coefficients, employing experimental values ...

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The rational design of coinage metal nanocarriers requires a mechanistic understanding of metal-drug binding and predictive descriptors that translate molecular interactions into design rules. Using DFT (B3LYP-D3BJ/def2-TZVP, SMD water), we systematically investigated the binding of 5-fluorouracil (5-FU) and levodopa (l-DOPA) to neutral and cationic homo- and heteronuclear dimers of Au, Ag, and Cu (Au2, Ag2, ...

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A wide series of substitutions in a subsystem of small radii cations M = Al, Cr, Fe, Ga, Sc is possible in rare-earth borates ReM3(BO3)4 with the huntite structure. However, the existence of these compounds where M = Mn still raises doubts. The study presents a synthetic approach developed in the framework of the flux method allowing for the required ...

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Density functional theory (DFT) is the workhorse of modern reactions and materials modeling. While the exact functional remains unknown, many approximations to it have been constructed either by hand-crafting functional forms to satisfy exact constraints or by machine learning. In this work, we show how both of these approaches can be fused to build both ...

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Added: June 3, 2026

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Wary R. R., Mahato B., Sharma N. et al., The Journal of Physical Chemistry Letters 2026 Vol. 17 No. 17 P. 5099–5107

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Water electrolysis is a key technology for sustainable energy conversion and hydrogen generation. Recently, high-entropy oxides (HEOs) have emerged as promising materials because they allow tuning of structural, electronic, and catalytic properties in multifunctional systems. Here, we report the synthesis of a multicomponent La(FeCoCuTiNiMnMgSnZn)O3 perovskite, and its hybridization with reduced graphene oxide (rGO) to form a ...

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We present a theoretical model of spin transitions in stacks of molecular layers. Our model captures the already established physics of these systems (thermal hysteretic transitions and crossovers) and suggests a way towards in situ control of this physics by means of an external electric field. Our results pave the way toward both temperature and voltage controllable organic ...

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