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Updated: Sep 24, 2025
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Recombination Dynamics in Thin-film Photovoltaic Materials via Time-resolved Microwave Conductivity
Published on: March 6, 2017
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Tunable microwave absorption of switchable complexes operating near room temperature
Olesia I Kucheriv1, Viktor V Oliynyk2, Volodymyr V Zagorodnii2
1Department of Chemistry, Taras Shevchenko National University of Kyiv 64 Volodymyrska St. Kyiv 01601 Ukraine illia.guralskyi@univ.kiev.ua.
RSC Advances
|May 6, 2022
Summary
Spin-crossover materials, such as [Fe(NH2trz)3]Br2 and [Fe(NH2trz)3](NO3)2, can switch microwave radiation absorption. This property is linked to their spin-state changes, enabling applications in tunable electronic devices.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Microwave Engineering
Background:
- Spin-crossover materials exhibit distinct low-spin and high-spin states.
- Switchable microwave absorption is crucial for advanced electronic devices.
- Coordination compounds offer tunable properties for material applications.
Purpose of the Study:
- To investigate the microwave absorption properties of spin-crossover coordination compounds.
- To demonstrate the thermoswitchable microwave absorbing capabilities of [Fe(NH2trz)3]Br2 and [Fe(NH2trz)3](NO3)2.
- To correlate microwave properties with spin-state transitions.
Main Methods:
- Variable temperature microwave reflection and transmission spectroscopy (26-37 GHz).
- Investigation of spin-crossover complexes [Fe(NH2trz)3]Br2 and [Fe(NH2trz)3](NO3)2.
- Differential scanning calorimetry and optical measurements for transition correlation.
Main Results:
- Significant differences in microwave interaction between high-spin and low-spin states were observed.
- Microwave transmission decreased notably upon transition to the high-spin state.
- Microwave permittivity changes were associated with spin crossover, influencing absorption properties.
Conclusions:
- Spin-crossover materials demonstrate thermoswitchable microwave absorption based on spin-state.
- These findings expand the application range of spin-crossover materials into microwave frequencies.
- The study contributes to a database for microwave absorbing properties of spin-crossover complexes.
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