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arXiv · 2002.00028

Valence instability across magnetostructural transition in USb$_2$

Z. E. Brubaker·Y. Xiao·P. Chow·C. Kenney-Benson·J. S. Smith·H. Cynn·C. Reynolds·N. P. Butch·R. J. Zieve·J. R. Jeffries
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Abstract

We have performed pressure dependent X-ray diffraction and resonant X-ray emission spectroscopy experiments on USb$_2$ to further characterize the AFM-FM transition occurring near 8 GPa. We have found the magnetic transition coincides with a tetragonal to orthorhombic transition resulting in a 17% volume collapse as well as a transient $\textit{f}$-occupation enhancement. Compared to UAs$_2$ and UAsS, USb$_2$ shows a reduced bulk modulus and transition pressure and an increased volume collapse at the structural transition. Except for an enhancement across the transition region, the $\textit{f}$-occupancy decreases steadily from 1.96 to 1.75.

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Z. E. Brubaker, Y. Xiao, P. Chow, C. Kenney-Benson, J. S. Smith, H. Cynn, C. Reynolds, N. P. Butch, R. J. Zieve, J. R. Jeffries. 2020-01-31. Valence instability across magnetostructural transition in USb$_2$. https://doi.org/10.1103/physrevb.101.085123

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