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arXiv · 0808.0838

Lattice Dynamics of LaFeAsO_{1-x}F_{x} and PrFeAsO_{1-y} via Inelastic X-Ray Scattering and First-Principles Calculation

T. Fukuda·A. Q. R. Baron·S. Shamoto·M. Ishikado·H. Nakamura·M. Machida·H. Uchiyama·S. Tsutsui·A. Iyo·H. Kito·J. Mizuki·M. Arai·H. Eisaki·H. Hosono
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Abstract

The lattice dynamics of LaFeAsO_{1-x}F_{x} (x=0, 0.1) and PrFeAsO_{1-y} (y~0.1) are investigated using inelastic x-ray scattering and ab-initio calculation. Measurements of powder samples provide an approximation to the phonon DOS, while dispersion is measured from a single crystal of PrFeAsO_{1-y}. A model that agrees reasonably well with all of the data at room temperature is built from results of ab-initio calculations by softening the strength of the Fe-As bond by 30%.

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T. Fukuda, A. Q. R. Baron, S. Shamoto, M. Ishikado, H. Nakamura, M. Machida, H. Uchiyama, S. Tsutsui, A. Iyo, H. Kito, J. Mizuki, M. Arai, H. Eisaki, H. Hosono. 2008-10-10. Lattice Dynamics of LaFeAsO_{1-x}F_{x} and PrFeAsO_{1-y} via Inelastic X-Ray Scattering and First-Principles Calculation. https://doi.org/10.1143/jpsj.77.103715

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