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arXiv · 1701.06819

The driving force for charge ordering in rare earth nickelates

Basudeb Mandal·Sagar Sarkar·Shishir Kumar Pandey·Priya Mahadevan·Cesare Franchini·A. J. Millis·D. D. Sarma
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Abstract

We show that charge ordering (more precisely, two-sublattice bond disproportionation) in the rare earth nickelate perovskites is intimately related to a negative charge transfer energy. By adding an additional potential on the Ni d states we are able to vary the charge tranfer energy and compute relaxed structures within an ab-initio framework. We show that the difference in Ni-O bond lengths and the value of the ordered state magnetic moment correlate with the charge transfer energy and that the transition to the bond-disproportionated state occurs when the effective charge transfer energy becomes negative.

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Basudeb Mandal, Sagar Sarkar, Shishir Kumar Pandey, Priya Mahadevan, Cesare Franchini, A. J. Millis, D. D. Sarma. 2017-01-24. The driving force for charge ordering in rare earth nickelates. https://arxiv.org/abs/1701.06819

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