Related Experiment Video
Updated: May 12, 2025

Using Cyclic Voltammetry, UV-Vis-NIR, and EPR Spectroelectrochemistry to Analyze Organic Compounds
Published on: October 18, 2018
Cooperativity of Electron Transfer Coupled Spin Transitions in a Tetranuclear Fe/Co Prussian Blue Analogue Revealed
Jan-Hendrik Borter1, Simindokht Gol Kar2, Sayan Kangsa Banik1
1Department of Dynamics at Surfaces, Max-Planck-Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany.
Abstract:
Cooperative intermolecular interactions, usually observed in solid state, can confer useful properties to stimuli-responsive spin transition materials. Here, we demonstrate for the first time intramolecular cooperativity between the two Fe-Co subunits of a molecular cyanido-bridged square Fe2Co2 Prussian blue analogue (PBA) in solution, which upon single photon excitation sequentially undergo electron transfer coupled spin transition (ETCST) from a diamagnetic low-spin (LS) to a paramagnetic high-spin (HS) state. Ultrafast UV-vis and IR pump-probe spectroscopies show that irradiation into the IVCT band of the LS state induces electron transfer within one Fe-Co subunit followed by fast (360 fs) SCO to an intermediate HS/LS species and a further ETCST event in the other Fe-Co subunit then occurs on a ns timescale. Kinetic analysis reveals that this cooperative switching of the two Fe-Co subunits is caused by two coupled equilibria favouring the second ETCST step, and the free energy landscape for the square Fe2Co2 system is determined experimentally.
More Related Videos
10:03Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
10:01Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase
Published on: December 4, 2017
Related Concept Videos
Colors and Magnetism
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
NMR Spectroscopy: Spin–Spin Coupling
Electron Paramagnetic Resonance (EPR) Spectroscopy: Organic Radicals
Spin–Spin Coupling: One-Bond Coupling
¹H NMR: Interpreting Distorted and Overlapping Signals
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
Cooperative Allosteric Transitions