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arXiv · 1705.10674

Combining electronic structure and many-body theory with large data-bases: a method for predicting the nature of 4f states in Ce compounds

Abstract

Here we present the first large scale investigation of electronic properties and correlated magnetism in Ce-based compounds accompanied by a systematic study of the electronic structure and 4f-hybridization function of a large body of Ce compounds. We systematically study the electronic structure and 4f-hybridization function of a large body of Ce compounds with the goal of elucidating the nature of the 4f states and their interrelation with the measured Kondo energy in these compounds. The hybridization function has been analyzed for more than 350 data sets of cubic Ce compounds using electronic structure theory that relies on a full-potential approach. We demonstrate that the strength of the hybridization function, evaluated in this way, allows us to draw precise conclusions about the degree of localization of the 4f states in these compounds. The theoretical results are entirely consistent with all experimental information, relevant to the degree of 4f localization for all investigated materials. Furthermore, a more detailed analysis of the electronic structure and the hybridization function allows us to make precise statements about Kondo correlations in these systems. The calculated hybridization functions, together with the corresponding density of states, reproduce the expected exponential behavior of the observed Kondo temperatures and prove a consistent trend in real materials. This trend allows us to predict which systems may be correctly identified as Kondo systems. A strong anti-correlation between the size of the hybridization function and the volume of the systems has been observed. Our approach demonstrates the predictive power of materials informatics when a large number of materials is used to establish significant trends which can be used to design new materials with desired properties.

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BibTeXRIS

Heike. C. Herper, Towfiq. Ahmed, John. M. Wills, Igor Di Marco, T. Björkman, Diana Iuşan, Alexander. V. Balatsky, Olle Eriksson. 2017-06-15. Combining electronic structure and many-body theory with large data-bases: a method for predicting the nature of 4f states in Ce compounds. https://doi.org/10.1103/physrevmaterials.1.033802

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