Profile
Synchrotron Next Generation Measurement Science Collaboration Research Division
Specially Appointed Professor IWAZUMI Toshiaki
- Themes
-
・Study of the structure and electronic state of materials using synchrotron radiation・Promotion of the development and application of synchrotron radiation measurement technology
- Keywords
- X-ray core spectroscopy, temperature and light induced phase transitions, strongly correlated electron materials
- Research Activities
-
Study of the structure and electronic state of materials by X-ray core spectroscopy
In the past, research into magnetic materials using quantum beams was dominated by neutron scattering, and X-rays were thought to be unsuitable for magnetic material research. However, neutron scattering requires large samples and is not suitable for examining small samples. Therefore, we have developed new measurement techniques using synchrotron radiation, such as magnetic Compton scattering, X-ray absorption magnetic circular dichroism, and resonant X-ray emission magnetic circular dichroism, and have been using these measurement techniques to promote research into magnetic materials.
Our newly developed measurement techniques are also useful for research into materials other than magnetic materials. Below we introduce a recent study on the structure and electronic state of Prussian blue analogues (PBAs).
PBAs are compounds whose main structure is the [Fe(CN)6] cluster, and they exhibit first-order phase transitions upon various physical stimuli. The electronic state of the [Fe(CN)6] cluster has been investigated using Fe 2p soft X-ray absorption, but two theoretical calculations with significantly different parameters have been proposed to interpret the results, and research into the electronic state has stalled.Therefore, by examining the Raman scattering component using resonant X-ray emission measurements, we were able to prove that one of the theoretical calculations was correct.Next, soft X-ray absorption and EXAFS measurements were performed on 10 types of PBAs samples, and the reproducibility of the soft X-ray absorption spectra was confirmed within the framework of correct theoretical calculations. It was found that the structure of the [Fe(CN)6] cluster did not change regardless of changes in the lattice constant, and that the electronic state of Fe changed continuously with the lattice constant.
