Vibrational Effects in X-ray Absorption Spectra of 2D Layered Materials

Abstract

With the examples of the C $K$-edge in graphite and the B $K$-edge in hexagonal BN, we demonstrate the impact of vibrational coupling and lattice distortions on the X-ray absorption near-edge structure (XANES) in 2D layered materials. Theoretical XANES spectra are obtained by solving the Bethe-Salpeter equation of many-body perturbation theory, including excitonic effects through the correlated motion of core-hole and excited electron. We show that accounting for zero-point motion is important for the interpretation and understanding of the measured X-ray absorption fine structure in both materials, in particular for describing the ${\sigma }^{\ast }$-peak structure.

& pages, 4 figures

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• Intrinsic localized mode and low thermal conductivity of PbSe
• Electronic Structure and Chemical Bonding of Amorphous Chromium Carbide Thin Films