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arXiv · 0903.1814

The electronic structure of {\em R}NiC$_2$ intermetallic compounds

J. Laverock·T. D. Haynes·C. Utfeld·S. B. Dugdale
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Abstract

First-principles calculations of the electronic structure of members of the $R$NiC$_2$ series are presented, and their Fermi surfaces investigated for nesting propensities which might be linked to the charge-density waves exhibited by certain members of the series ($R$ = Sm, Gd and Nd). Calculations of the generalized susceptibility, $\chi_{0}({\bf q},\omega)$, show strong peaks at the same ${\bf q}$-vector in both the real and imaginary parts for these compounds. Moreover, this peak occurs at a wavevector which is very close to that experimentally observed in SmNiC$_2$. In contrast, for LaNiC$_2$ (which is a superconductor below 2.7K) as well as for ferromagnetic SmNiC$_2$, there is no such sharp peak. This could explain the absence of a charge-density wave transition in the former, and the destruction of the charge-density wave that has been observed to accompany the onset of ferromagnetic order in the latter.

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J. Laverock, T. D. Haynes, C. Utfeld, S. B. Dugdale. 2009-03-10. The electronic structure of {\em R}NiC$_2$ intermetallic compounds. https://doi.org/10.1103/physrevb.80.125111

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