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Hard X-ray-Induced Valence Tautomeric Interconversion in Cobalt-o-Dioxolene Complexes.
Thiago M Francisco1, William J Gee2, Helena J Shepherd2
1Physics Department, Federal University of Minas Gerais , Belo Horizonte, 31270-901, Brazil.
The Journal of Physical Chemistry Letters
|September 15, 2017
Summary
Hard X-rays can trigger valence tautomeric interconversion (VTI) in cobalt complexes. The extent of this VTI process is influenced by X-ray intensity and exposure time, impacting low-temperature studies.
Area of Science:
- Coordination Chemistry
- Materials Science
- Solid-State Physics
Background:
- Valence tautomeric interconversion (VTI) involves reversible intramolecular electron transfer and spin state changes in metal complexes.
- These complexes exhibit switchable electronic states, known as redox isomers.
- Understanding VTI is crucial for developing responsive materials.
Purpose of the Study:
- To investigate the effect of hard synchrotron X-ray radiation on VTI in a cobalt complex at low temperatures.
- To determine if X-ray radiation can induce VTI and how its parameters influence the process.
- To assess the potential impact of X-ray probing on low-temperature structural studies.
Main Methods:
- Single-crystal X-ray diffraction studies were performed on [Co(diox)2(4-CN-py)2]·benzene complex (1) at temperatures between 30-100 K.
- Hard synchrotron X-ray radiation of varying intensities was used as the stimulus.
- Structural analysis was conducted to observe changes related to VTI.
Main Results:
- Hard X-ray radiation was demonstrated to induce valence tautomeric interconversion (VTI) in the studied cobalt complex for the first time.
- The molar fraction of VTI was found to be dependent on both X-ray intensity and exposure time.
- This indicates that X-ray probing can alter the structural and electronic properties of materials at low temperatures.
Conclusions:
- X-ray radiation can act as an external trigger for VTI in metal complexes.
- The findings highlight the importance of considering X-ray-induced effects in low-temperature crystallographic studies.
- This research offers new insights into VTI phenomena and photoresponsive complexes.
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