A study of electronic properties in quasicrystals with resonant X-ray flourescence

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The objective of this report is to clarify the electronic structure in some quasicrystals by using resonant X-ray fluorescence spectroscopy, which has been developed recent decade. (1) Mn-Kβ photoemission spectra in four kinds of alloy of quasicrystals and (2) Lα and Lβ spectra in Rear Earth systems were measured in three beam time at the photon factory in High Energy Accelerator Research Organization.The dependence Mn Kβ_<1,3> (3p->1s) photo emission spectra on the incident photon energy were measured in the quasicrystals of F type icosahedral Al-Pd-Mn (i-Al-Pd-Mn), P type icosahedral Al-Mn-Si (i-Al-Mn-Si), α-phase which is approximant of i-Al-Mn-Si and decagonal Al-Mn-Fe-Ge (d-Al-Mn-Fe-Ge). For d-Al-Mn-Fe-Ge, Fe Kβ_<1,3> spectrum was also measured. Manganese compounds (oxides and KMnO_4) spectra were also collected as a standard of non-metallic materials. All these spectra of quasicrystals shows very small Kβ' peak, the ratio of which to Kβ_<1,3> means the splitting between density o … More f state of high spin and low spin, and were similar to that of KMnO4 (+7). The spectrum of i-Al-Mn-Si was almost consistent with α phase. It indicates that the electronic structures of them are very close although the structure α phase has only the second approximate structure to the Al-Mn-Si quasicrystal. The whole profile i-Al-Pd-Mn was also similar to those but there was a characteristic hump at the energy between Kβ_<1,3> peak and Kβ', which hump has not been reported in any other materials. The peak height ratio of Kβ' to Kβ_<1,3> in d-Al-Mn-Fe-Ge is the highest in these quasicrystal. It may originate in the splitting of d-state because only this system shows ferromagnetism in these quasicrystals.The photoemission spectra of Lα_<1,2> and Lβ_1 in F-type icosahedral Zn-Mg-RE (RE : Ho, Dy) were measured at room temperature. They shows the large quadropole peak which peak energy increase with increasing in the incident X-ray energy. The degree of quadropole splitting are almost the same in both system although the shape of peaks have small difference between them. Less