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arXiv · 0907.1745

Metal-insulator transition in NiS$_{2-x}$Se$_x$

J. Kunes·L. Baldassarre·B. Schachner·K. Rabia·C. A. Kuntscher·Dm. M. Korotin·V. I. Anisimov·J. A. McLeod·E. Z. Kurmaev·A. Moewes
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Abstract

The origin of the gap in NiS2 as well as the pressure- and doping-induced metal-insulator transition in the NiS2-xSex solid solutions are investigated both theoretically using the first-principles band structures combined with the dynamical mean-field approximation for the electronic correlations and experimentally by means of infrared and x-ray absorption spectroscopies. The bonding-antibonding splitting in the S-S (Se-Se) dimer is identified as the main parameter controlling the size of the charge gap. The implications for the metal-insulator transition driven by pressure and Se doping are discussed.

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J. Kunes, L. Baldassarre, B. Schachner, K. Rabia, C. A. Kuntscher, Dm. M. Korotin, V. I. Anisimov, J. A. McLeod, E. Z. Kurmaev, A. Moewes. 2010-03-27. Metal-insulator transition in NiS$_{2-x}$Se$_x$. https://doi.org/10.1103/physrevb.81.035122

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