Soft X-ray emission spectroscopy on chemical states of 3d-transition metal elements with SEM

Terauchi, Masami*; Takahashi, Hideyuki*; Murano, Takanori*; Imazono, Takashi; Koike, Masato; Nagano, Tetsuya*; Koeda, Masaru*

The chemical bonding state of titanium dioxide is clearly revealed by using in combination with soft X-ray grating spectrometer and SEM. In a simple ionic model considered as TiO in TiO, Ti ion has no 3 electron, but Ti emission spectra resulting from the electron transition from 3 valance band to the core holes can be observed. Thus, it indicates that the emissions of Ti originates from the covalent bonding between Ti and O atoms. The peak position of the band of TiO, brookite, is found to be placed on the lower energy side than that of metal-Ti, but it is opposite to the theoretical prediction. This means that the intensity profile is not suitable for probing chemical shift due to the influence from the density of states of the valence band. On the other hand, the peak shift of the band caused by transitions between inner-shell levels is on the higher energy side than that of metal-Ti. It is found to be reasonable for the cation chemical shift.