Robust spin-filtering and current-switching in a photochromic Fe(II) spin-crossover complex
Jing Huang1, Yiting Zhuo1, Mingdi Yang1
1School of Materials and Chemical Engineering, Anhui Jianzhu University, Hefei, Anhui 230601, China. youthmd98@ahjzu.edu.cn.
Nanoscale
|July 14, 2025
Summary
Photochromic iron(II) spin-crossover (SCO) complexes exhibit magnetic bistability, enabling their use as spin-switches. These complexes demonstrate a nearly perfect spin-filtering effect and current-switching behavior, crucial for molecular spintronics.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Supramolecular Chemistry
Background:
- Spin-crossover (SCO) complexes with magnetic bistability are promising for molecule-based devices.
- Photochromic diarylethene-based ligands enable reversible light-induced switching between SCO isomers.
Purpose of the Study:
- To explore the spin-resolved electronic and transport properties of photochromic Fe(II) SCO complexes.
- To investigate the potential of these complexes as spin-switches in molecular spintronics.
Main Methods:
- First-principles calculations.
- Non-equilibrium Green's function (NEGF) technique.
- Simulations of molecular junctions with Au(111) electrodes.
Main Results:
- The high-spin, open-ring (HS-O) isomer is energetically favored over the low-spin, closed-ring (LS-C) isomer by 0.59 eV.
- A nearly perfect spin-filtering effect was observed for the HS-O isomer, with preferential transport of spin-down electrons.
- Significant current-switching behavior was demonstrated between the HS-O (ON state) and LS-C (OFF state) isomers.
Conclusions:
- Photochromic Fe(II) SCO complexes exhibit excellent spin-filtering and current-switching properties.
- These SCO complexes hold great potential for applications in molecular spintronics and future electronic devices.
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