%0 Journal Article
%A Nakayama, Yasuo
%A Bocquet, François C.
%A Tsuruta, Ryohei
%A Soubatch, Serguei
%A Tautz, F. Stefan
%T Anisotropic dispersion of excitonic bands of the single-crystal pentacene (001) surface as measured by low-energy angle-resolved high-resolution electron energy-loss spectroscopy
%J Journal of electron spectroscopy and related phenomena
%V 279
%@ 0368-2048
%C New York, NY [u.a.]
%I Elsevier
%M FZJ-2025-01649
%P 147514
%D 2025
%X Low-energy high-resolution electron energy-loss spectroscopy (HREELS) is a useful technique for the charac-terization of various excitation processes at solid surfaces. However, no successful work has been reported onmolecular single-crystal samples yet. In the present study, low-energy angle-resolved HREELS measurementswere conducted on single-crystal pentacene, an organic semiconductor. The results confirmed the excitonicbands exhibiting energy–momentum dispersion and anisotropy of these depending on the surface crystallo-graphic directions, corroborating the occurrence of exciton delocalization, contrary to the ordinary notion of theFrenkel exciton for weakly interacting van der Waals molecular solids. The present results demonstrate that low-energy angle-resolved HREELS is applicable to the precise examination of the excitonic characteristics of solid-state surfaces, even for molecular semiconductor single crystals.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:001420630000001
%R 10.1016/j.elspec.2025.147514
%U https://juser.fz-juelich.de/record/1038812