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arXiv · 2012.07010

Lattice dynamics of KAgF3 perovskite, unique 1D antiferromagnet

Kacper Koteras·Jakub Gawraczynski·Mariana Derzsi·Zoran Mazej·Wojciech Grochala
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Abstract

Theoretical DFT calculations using GGA+U and HSE06 frameworks enabled vibrational mode assignment and partial (atomic) phonon DOS determination in KAgF3 perovskite, a low-dimensional magnetic fluoroargentate(II). Twelve bands in the spectra of KAgF3 were assigned to either IR active or Raman active modes, reaching very good correlation with experimental values (R2>0.997). Low-temperature Raman measurements indicate that the intriguing spin-Peierls-like phase transition at 230 K is an order-disorder transition and it does not strongly impact the vibrational structure of the material.

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Kacper Koteras, Jakub Gawraczynski, Mariana Derzsi, Zoran Mazej, Wojciech Grochala. 2020-12-13. Lattice dynamics of KAgF3 perovskite, unique 1D antiferromagnet. https://doi.org/10.3390/chemistry3010007

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