Interplay of negative pressure and hydrogen chemical effects in CeRhSn from first principles

2008/03/25 by Adel F. Al Alam, A. F. Al Alam, S. F. Matar +4 · 6 citations
Chemistry · Materials Science · Physics and Astronomy · #Cerium #Chemistry #Computational chemistry #Electronic structure #Hydride #Hydrogen #Hydrogen Storage and Materials #Inorganic chemistry #Intermetallic #Materials science #Nuclear Materials and Properties #Organic chemistry #Physical chemistry #Physics #Rare-earth and actinide compounds #Thermodynamics #Valence (chemistry) #cond-mat.mtrl-sci #cond-mat.str-el

paper · pdf · doi:10.1140/epjb/e2008-00369-4

published in The European Physical Journal B 65(4), 491-498 (Springer Science+Business Media)

arxiv created 2008/03/25 · openalex publication_date 2008/10/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

Investigations within the local spin density functional theory (LSDF) of the intermetallic hydride system \rm CeRhSnH_x were carried out for discrete model compositions in the range 0.33 ≤ x_H ≤ 1.33 . The aim of this study is to assess the change of the cerium valence state in the neighborhood of the experimental hydride composition, \rm CeRhSnH_0.8 . In agreement with experiment, the analyses of the electronic and magnetic structures and of the chemical bonding properties point to trivalent cerium for 1 ≤ x_H ≤ 1.33 . In contrast, for lower hydrogen amounts the hydride system stays in an intermediate-valent state for cerium, like in \rm CeRhSn . The influence of the insertion of hydrogen is addressed from both the volume expansion and chemical bonding effects. The latter are found to have the main influence on the change of Ce valence character. Spin polarized calculations point to a finite magnetic moment carried by the Ce 4f states; its magnitude increases with x_H in the range 1 ≤ x_H ≤ 1.33 .

Citations

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