Femtosecond Spin-State Switching Dynamics of Fe(II) Complexes Condensed in Thin Films
The tailoring of spin-crossover films has made significant progress over the past decade, mostly motivated by the prospect in technological applications. In contrast to spin-crossover complexes in solution, the investigation of the ultrafast switching in spin-crossover films has remained scarce. Combining the progress in molecule synthesis and film growth with the opportunities at X-ray free-electron lasers, we study the photoinduced spin-state switching dynamics of a molecular film at room temperature. The subpicosecond switching from the <i>S</i> = 0 low-spin ground state to the <i>S</i> = 2 high-spin state is monitored by analyzing the transient evolution of the Fe L<sub>3</sub> X-ray absorption edge fine structure, i.e. element-specifically at the switching center of the Fe(II) complex. Our measurements show the involvement of an intermediate state in the switching. At large excitation fluences, the fraction of high-spin molecules saturates at ≈50%, which is likely due to molecule-molecule interaction within the film.
Authors
- Senthil Kumar Kuppusamy (ORCID: https://orcid.org/0000-0002-1501-7759)
- Robert Carley (ORCID: https://orcid.org/0000-0002-0015-7089)
- David Hickin
- Manuel Gruber (ORCID: https://orcid.org/0000-0002-8353-4651)
- Andrea Eschenlohr (ORCID: https://orcid.org/0000-0002-0814-3511)
- Lea Kämmerer (ORCID: https://orcid.org/0000-0002-3944-2696)
- Benjamin E. Van Kuiken (ORCID: https://orcid.org/0000-0002-3650-7765)
- Andreas Scherz (ORCID: https://orcid.org/0000-0001-8187-7178)
- Heiko Wende (ORCID: https://orcid.org/0000-0001-8395-3541)
- Cammille Carinan
- Laurent Mercadier (ORCID: https://orcid.org/0000-0003-0606-0461)
- Mario Ruben (ORCID: https://orcid.org/0000-0002-7718-7016)
- Martin Teichmann (ORCID: https://orcid.org/0000-0003-4215-9792)
- Felix Tuczek (ORCID: https://orcid.org/0000-0001-7290-9553)
- Loïc Le Guyader (ORCID: https://orcid.org/0000-0002-5731-3724)
- Giuseppe Mercurio (ORCID: https://orcid.org/0000-0003-4221-6670)
- U. Bovensiepen (ORCID: https://orcid.org/0000-0002-1506-4491)
- Katharina Ollefs (ORCID: https://orcid.org/0000-0002-2301-4670)
- Jan Grunwald
- K. Sokolowski-Tinten (ORCID: https://orcid.org/0000-0002-7979-5357)
- Peter Kratzer (ORCID: https://orcid.org/0000-0001-5947-1366)
- Carolin Schmitz‐Antoniak (ORCID: https://orcid.org/0000-0002-8450-3515)
- Gérald Kämmerer
- Natalia Gerasimova (ORCID: https://orcid.org/0009-0000-0486-367X)
- Tobias Lojewski
Institutions
- Karlsruhe Institute of Technology (DE)
- Christian-Albrechts-Universität zu Kiel (DE)
- Technical University of Applied Sciences Wildau (DE)
- Institut de Science et d'Ingénierie Supramoléculaires (FR)
- University of Duisburg-Essen (DE)
- European X-Ray Free-Electron Laser (DE)
Publication Details
- Journal
- ACS Nano
- Published
- 2024-12-12
- DOI
- https://doi.org/10.1021/acsnano.4c05123
- Citations
- 1
- Primary Topic
- Magnetism in coordination complexes
- Type
- article
- Field-Weighted Citation Impact
- 0.12
Funders
- Deutsche Forschungsgemeinschaft