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Published on: June 9, 2023
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Structural dynamics of a thermally silent triiron(II) spin crossover defect grid complex
Jose de Jesus Velazquez-Garcia1, Krishnayan Basuroy1, Darina Storozhuk1
1Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany. jose.velazquez@desy.de.
Dalton Transactions (Cambridge, England : 2003)
|September 1, 2023
Summary
This study investigates a defect triiron metallogrid
Area of Science:
- Coordination Chemistry
- Materials Science
- Crystallography
Background:
- Spin crossover (SCO) complexes are crucial for electronic devices.
- Understanding structural dynamics during spin transitions is key for applications.
- Defect metallogrids offer unique properties for cooperative phenomena.
Purpose of the Study:
- To investigate the structural evolution of a defect triiron(II) metallogrid (FE3) under thermal and light stimuli.
- To elucidate the out-of-equilibrium dynamics of SCO complexes.
- To explore the role of structural flexibility in intermolecular cooperativity.
Main Methods:
- Single-crystal X-ray diffraction at variable temperatures.
- Time-resolved photocrystallography with picosecond (ps) laser excitation.
- Analysis of structural changes at picosecond (ps) and nanosecond (ns) timescales.
Main Results:
- The defect triiron metallogrid (FE3) does not exhibit a thermal spin transition.
- Photoexcitation reveals distinct photoinduced (ps) and elastic (ns) structural steps.
- FE3 shows local and long-range lattice distortions, similar to related tetrairon grids.
- The defect grid's lifetime of the photoinduced high spin (HS) state is shorter than in tetranuclear analogues.
Conclusions:
- Defect metallogrids possess unique structural flexibility beneficial for intermolecular cooperativity.
- The study reveals the initial out-of-equilibrium dynamics of a thermally silent SCO metallogrid.
- Global nuclearity influences the lifetime of photoinduced high spin states in SCO complexes.
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