We have determined the lattice dynamics of molybdenum at high pressure to 37 GPa using high-resolution inelastic x-ray scattering. Over the investigated pressure range, we find a significant decrease in the H-point phonon anomaly. We also present calculations based on density functional theory that accurately predict this pressure dependence. Based on these results, we infer that the likely explanation for the H-point anomaly in molybdenum is strong electron-phonon coupling, which decreases upon compression due to the shift of the Fermi level with respect to the relevant electronic bands.
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http://dx.doi.org/10.1103/PhysRevLett.96.115502 | DOI Listing |
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Chongqing Jiaotong University, No. 66, Xuefu Avenue, Nanan District, Chongqing City, Chongqing, Chongqing, 400074, CHINA.
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Faculty of Chemistry, University of Warsaw, Pasteura 1, Warsaw, 02-093, Poland.
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