Stepwise spin-state switching in a manganese(III) complex
Subrata Ghosh1, Sukanya Bagchi, Mayurika Das
1Solid State and Structural Chemistry Unit, Indian Institute of Science, Sir C V Raman Road, Bangalore 560012, India. mondal@iisc.ac.in.
Dalton Transactions (Cambridge, England : 2003)
|October 20, 2020
Summary
This study details a manganese(III) complex with a flexible ligand, exhibiting reversible, temperature-dependent spin-state switching between high-spin, low-spin, and intermediate states.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Coordination Chemistry
Background:
- Manganese complexes are crucial in catalysis and materials science.
- Spin-state switching in metal complexes offers tunable electronic and magnetic properties.
Purpose of the Study:
- To synthesize and characterize a novel mononuclear manganese(III) complex.
- To investigate its spin-state switching behavior and electrochemical properties.
Main Methods:
- Single-crystal X-ray diffraction at various temperatures.
- Magnetic, spectroscopic, and electrochemical studies.
- Analysis of structural and electronic transitions.
Main Results:
- The manganese(III) complex features an MnN4O2 octahedral coordination.
- Reversible two-step spin-state switching observed at 168 K (gradual) and 103 K (abrupt).
- Three distinct spin states (high-spin, low-spin, intermediate) identified during switching.
- Quasi-reversible reduction and oxidation of the manganese(III) center were electrochemically confirmed.
Conclusions:
- The synthesized manganese(III) complex exhibits complex spin-state dynamics.
- The tunable spin states and accessible redox states suggest potential applications in molecular switches and sensors.
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