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 σ∗-peak structure.
@article{arxiv.1904.10194,
title = {Vibrational Effects in X-ray Absorption Spectra of 2D Layered Materials},
author = {Weine Olovsson and Teruyasu Mizoguchi and Martin Magnuson and Stefan Kontur and Olle Hellman and Isao Tanaka and Claudia Draxl},
journal= {arXiv preprint arXiv:1904.10194},
year = {2019}
}