Structure of the ground and excited states in the Co2FeSi Heusler alloy according to the resonant photoemission data

• Published in: Journal of structural chemistry 2015-06, Vol.56 (3), p.511-516
• Main Authors: Grebennikov, V. I., Buling, A., Neumann, M., Marchenkov, V. V., Kuznetsova, T. V.
• Format: Article
• Language: English
• Subjects: 2013; Atomic; Atomic/Molecular Structure and Spectra; Chemistry; Chemistry and Materials Science; Inorganic Chemistry; Molecular; October 7–11; Optical and Plasma Physics; Physical Chemistry; Proceedings of the Conference “X-Ray and Electronic Spectra and Chemical Bond (XESCB)” Novosibirsk Scientific Center; Solid State Physics
• ISSN: 0022-4766; 1573-8779
• DOI: 10.1134/S002247661503018X

The electronic structure of the ground and low-energy excited states of the Co 2 FeSi Heusler alloy is investigated by the methods of X-ray absorption spectroscopy (XAS) and resonant X-ray photoelectron spectroscopy (RXPS). The orbital and spin magnetic moments of the iron and cobalt atoms are determined in a 0.05 T magnetic field. A comparative analysis is given of two amplifier channels of the valence band photoemission at the resonant excitation of the 2 p level: elastic and Auger electron emission. A decrease in the magnetic moment of the atom leads to a qualitative change in the resonant photoemission spectrum. The valence electron shake-up at a sudden appearance of a 2 p core photohole on the iron atoms leads to multiple formations of low-energy electron-hole pairs and gives rise to continuous losses in the XPS and XAS spectra. Shake-up in the cobalt atoms with great probability gives rise to one electron-hole pair with an energy of 4 eV, which is manifested as a satellite band in the above mentioned spectra. The mentioned feautures are closely related to semimetal ferromagnetism.