The Ba 4d-4f giant dipole resonance in complex Ba/Si compounds

Journal Article · Wed Aug 06 00:00:00 EDT 2014 · J. Phys. B

DOI:https://doi.org/10.1088/0953-4075/47/4/045102· OSTI ID:1149166

Sahle, Ch. J.; Sternemann, C.; Sternemann, H.; Tse, J. S.; Gordon, R. A.; Desgreniers, S.; Maekawa, S.; Yamanaka, S.; Lehmkuhler, F.; Wieland, D. C.F.; Mende, K.; Huotari, S.; Tolan, M. ^[1]

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1. TU Dortmund

The shape of the Ba 4d–4f giant dipole resonance is studied for Ba atoms embedded inside complex Si networks covering structures consisting of Si nanocages and nanotubes, i.e. the clathrate Ba₈Si₄₆, the complex compound BaSi₆, and the semiconducting BaSi₂. Here, non-resonant x-ray Raman scattering is used to investigate confinement effects on the shape of the giant resonance in the vicinity of the Ba NIV, V-edge. The distinct momentum transfer dependence of the spectra is analyzed and discussed. The measurements are compared to calculations of the giant resonance within time-dependent local density approximation in the dipole limit. No modulation of the giant resonance's shape for Ba atoms confined in different local environments was observed, in contrast to the calculations. The absence of such shape modulation for complex Ba/Si compounds is discussed providing important implications for further studies of giant resonance phenomena utilizing both theory and experiment.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
• Sponsoring Organization: FOREIGN
• OSTI ID: 1149166
• Journal Information: J. Phys. B, Vol. 47, Issue 2014
• Country of Publication: United States
• Language: ENGLISH