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Photoemission and x-ray absorption study of MgC_(1-x)Ni_3

J. H. Kim·J. S. Ahn·Jinsoo Kim·Min-Seok Park·S. I. Lee·E. J. Choi·S. -J. Oh
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Abstract

We investigated electronic structure of MgC_(1-x)Ni_3 with photoemission and x-ray absorption spectroscopy. Both results show that overall band structure is in reasonable agreement with band structure calculations including the existence of von Hove singularity (vHs)near E_F. However, we find that the sharp vHs peak theoretically predicted near the E_F is substantially suppressed. As for the Ni core level and absorption spectrum, there exist the satellites of Ni 2p which have a little larger energy separation and reduced intensity compared to the case of Ni-metal. These facts indicate that correlation effects among Ni 3d electrons may be important to understand various physical properties.

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J. H. Kim, J. S. Ahn, Jinsoo Kim, Min-Seok Park, S. I. Lee, E. J. Choi, S. -J. Oh. 2002-09-04. Photoemission and x-ray absorption study of MgC_(1-x)Ni_3. https://doi.org/10.1103/physrevb.66.172507

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