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Electron-hole and plasmon excitations in 3d transition metals: Ab initio calculations and inelastic x-ray scattering measurements

I. G. Gurtubay·J. M. Pitarke·Wei Ku·A. G. Eguiluz·B. C. Larson·J. Tischler·P. Zschack·K. D. Finkelstein
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Abstract

We report extensive all-electron time-dependent density-functional calculations and nonresonant inelastic x-ray scattering measurements of the dynamical structure factor of 3d transition metals. For small wave vectors, a plasmon peak is observed which is well described by our calculations. At large wave vectors, both theory and experiment exhibit characteristic low-energy electron-hole excitations of d character which correlate with the presence of d bands below and above the Fermi level. Our calculations, which have been carried out in the random-phase and adiabatic local-density approximations, are found to be in remarkable agreement with the measured dynamical structure factor of Sc and Cr at energies below the semicore onset energy (M-edge) of these materials.

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I. G. Gurtubay, J. M. Pitarke, Wei Ku, A. G. Eguiluz, B. C. Larson, J. Tischler, P. Zschack, K. D. Finkelstein. 2005-08-29. Electron-hole and plasmon excitations in 3d transition metals: Ab initio calculations and inelastic x-ray scattering measurements. https://doi.org/10.1103/physrevb.72.125117

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