Characteristic chemical shift of quasicrystalline alloy Al53Si27Mn20 studied by EELS and SXES |
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| Authors: | S Koshiya M Terauchi AP Tsai |
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| Institution: | 1. Institute of Multidisciplinary Research for Advanced Material, Tohoku University , 2-1-1 Katahira, Aoba-ku , Sendai 980-8577 , Japan koshiya@mail.tagen.tohoku.ac.jp;3. Institute of Multidisciplinary Research for Advanced Material, Tohoku University , 2-1-1 Katahira, Aoba-ku , Sendai 980-8577 , Japan |
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| Abstract: | Chemical shifts of all constituent atoms for amorphous (Am), quasicrystalline (QC) and crystalline (Cryst) alloys of Al53Si27Mn20 were investigated for the first time by high energy-resolution electron energy-loss spectroscopy (EELS) and soft-X-ray emission spectroscopy (SXES). Among Al L-shell excitation EELS spectra of Am, QC and Cryst alloys, only QC alloy showed an apparent chemical shift to the larger binding energy side by 0.4?eV. In Al-Kα and Si-Kα emission SXES spectra of these alloys, only QC alloy showed a chemical shift to the larger binding energy side by 4?eV for Al-Kα and 6?eV for Si-Kα. These chemical shift values are comparable to those of corresponding metal oxides. This indicates a smaller amount of valence charge at Al and Si atomic sites in QC alloy. On the other hand, Mn-L SXES spectra did not show any chemical shift. Therefore, the decreased charge from Al and Si sites should be distributed between atomic sites, indicating the presence of covalent bonding nature for QC ordered alloy. |
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| Keywords: | quasicrystalline alloy electronic structure spectroscopy chemical shift Al–Si–Mn alloy |
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