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X-ray photoemission study of NiS_{2-x}Se_x (x = 0.0 - 1.2)

S. R. Krishnakumar·D. D. Sarma
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Abstract

Electronic structure of NiS_{2-x}Se_x system has been investigated for various compositions (x) using x-ray photoemission spectroscopy. An analysis of the core level as well as the valence band spectra of NiS_2 in conjunction with many-body cluster calculations provides a quantitative description of the electronic structure of this compound. With increasing Se content, the on-site Coulomb correlation strength (U) does not change, while the band width W of the system increases, driving the system from a covalent insulating state to a pd-metallic state.

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S. R. Krishnakumar, D. D. Sarma. 2003-08-18. X-ray photoemission study of NiS_{2-x}Se_x (x = 0.0 - 1.2). https://doi.org/10.1103/physrevb.68.155110

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