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Proton-driven coordination-induced spin state switch (PD-CISSS) of iron(ii) complexes
René Nowak1, Eko Adi Prasetyanto, Luisa De Cola
1Anorganische Chemie II, Universität Bayreuth, Universitätsstr. 30, NW I, 95440 Bayreuth, Germany. weber@uni-bayreuth.de.
Chemical Communications (Cambridge, England)
|January 4, 2017
Summary
This study demonstrates reversible spin state switching in iron(II) complexes using pH changes. These findings are applicable to both solution and zeolite-encapsulated materials, impacting spin crossover research.
Area of Science:
- Coordination Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Iron(II) complexes exhibit spin crossover (SCO) properties, transitioning between low-spin and high-spin states.
- Controlling SCO behavior is crucial for developing molecular switches and sensors.
- pH-induced spin state switching offers a promising avenue for external control.
Purpose of the Study:
- To investigate the pH-dependent spin state switching of tris(bipyridine)iron(II) and bis(2,6-bis(1H-pyrazol-3-yl)pyridine)iron(II) complexes.
- To explore the reversibility of this spin state switch in solution and within a zeolite matrix.
- To characterize the spin state changes using various spectroscopic and magnetic techniques.
Main Methods:
- Proton Nuclear Magnetic Resonance (¹H-NMR) spectroscopy
- UV-Visible (UV-Vis) spectroscopy
- Magnetic susceptibility measurements
- Relaxivity measurements
- Encapsulation in zeolite matrices
Main Results:
- Demonstrated completely reversible spin state switching in both iron(II) complexes upon pH variation.
- Confirmed spin state changes in solution and when encapsulated within zeolite materials.
- Spectroscopic and magnetic data corroborated the observed spin crossover behavior.
Conclusions:
- pH is an effective trigger for reversible spin state switching in these iron(II) complexes.
- The spin crossover phenomenon is maintained in composite materials within a zeolite matrix.
- This work provides insights into designing pH-responsive molecular spin crossover systems.
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