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Updated: Nov 8, 2025
09:33
Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
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A photo-induced spin crossover based molecular switch and spin filter operating at room temperature
Nicolás Montenegro-Pohlhammer1, Rocío Sánchez-de-Armas, Carmen J Calzado
1Laboratory of Theoretical Chemistry, Faculty of Chemistry and Biology, University of Santiago de Chile (USACH), 9170022, Santiago, Chile. nicolas.montenegro.p@usach.cl.
Dalton Transactions (Cambridge, England : 2003)
|April 26, 2021
Summary
This study investigates a nickel-porphyrin complex (NiTPP-PAPy) on a gold surface. Researchers found its light-induced spin switching and unique electronic properties are maintained, suggesting potential for room-temperature molecular spintronic devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Computational Chemistry
Background:
- Nickel-porphyrin functionalized with phenylazopyridine (NiTPP-PAPy) exhibits room-temperature light-induced spin crossover.
- This phenomenon holds promise for molecular-based electronic devices.
Purpose of the Study:
- To investigate the adsorption and transport properties of NiTPP-PAPy on an Au(111) surface.
- To determine if photoinduced spin switching is preserved upon deposition.
- To explore potential applications in molecular switches and spintronic devices.
Main Methods:
- Density Functional Theory (DFT) and Wave Function (WFT) methodologies.
- DFT with Non-Equilibrium Green's Function (NEGF) calculations for transport properties.
- Time-Dependent DFT (TD-DFT) for confirmation.
Main Results:
- NiTPP-PAPy strongly adsorbs on the Au(111) surface in both high spin (HS) and low spin (LS) states.
- Photoinduced spin switching is preserved after adsorption, confirmed by WFT and TD-DFT.
- Significantly higher current in HS than LS configuration; current in ferromagnetic junctions is highly spin-polarized.
Conclusions:
- The NiTPP-PAPy complex retains its photoresponsive spin crossover on a gold surface.
- Its distinct transport properties enable potential applications as molecular switches and spin filters.
- The complex shows promise for room-temperature spintronic devices.
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