How strongly correlated is MnSi?

F. Carbone; M. Zangrando; A. Brinkman; A. Nicolaou; F. Bondino; E. Magnano; A. A. Nugroho; Th. Jarlborg; F. Parmigiani; D. van der Marel

arXiv · cond-mat/0601509

How strongly correlated is MnSi?

F. Carbone·M. Zangrando·A. Brinkman·A. Nicolaou·F. Bondino·E. Magnano·A. A. Nugroho·Th. Jarlborg·F. Parmigiani·D. van der Marel

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Abstract

We present an experimental study of the electronic structure of MnSi. Using X-ray Absorption Spectroscopy, X-ray photoemission and X-ray fluorescence we provide experimental evidence that MnSi has a mixed valence ground state. We show that self consistent LDA supercell calculations cannot replicate the XAS spectra of MnSi, while a good match is achieved within the atomic multiplet theory assuming a mixed valence ground state. We discuss the role of the electron-electron interactions in this compound and estimate that the valence fluctuations are suppressed by a factor of 2.5, which means that the Coulomb repulsion is not negligible.

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F. Carbone, M. Zangrando, A. Brinkman, A. Nicolaou, F. Bondino, E. Magnano, A. A. Nugroho, Th. Jarlborg, F. Parmigiani, D. van der Marel. 2006-01-23. How strongly correlated is MnSi?. https://arxiv.org/abs/cond-mat/0601509

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