[1Dp01-09] Surface Science(SS1) Physical Property

[1Dp03] Proving weak electronic interaction between organic and inorganic materials: a study of pentacene monolayer on graphite

*Yuri Hasegawa¹, Takuma Yamaguchi², Matthias Meissner¹, Takahiro Ueba¹, Fabio Bussolotti¹, Shin-ichiro Ideta³, Kiyohisa Tanaka^3,2, Susumu Yanagisawa⁴, Satoshi Kera^1,2,3 (1. Department of Photo-Molecular Science, Institute for Molecular Science, 2. The Graduate University for Advanced Studies (SOKENDAI), 3. UVSOR Synchrotron Facility, Institute for Molecular Science, 4. Department of Physics and Earth Sciences, Faculty of Science, University of the Ryukyus)

The interaction between organic-inorganic materials is important to understand the mechanism of the formation of the interfacial electronic state. In this study, the pentacene (PEN) monolayer on graphite substrates was measured by low-energy angle-resolved ultraviolet photoelectron spectroscopy (LE-ARUPS). Although PEN/graphite is a well-known physisorption system, tiny changes are observed in the occupied state, therefore, the unoccupied states are expected to be significantly affected. In the LE-ARUPS measurement, the dispersive convex band is observed as a constant final state (CFS) overlapping with the discrete non-dispersive molecular band. The dispersive band consists of positive and negative intensities depending on the excitation energy, indicating Fano resonance involving a discrete molecular state and a continuum state. The continuum state could originate from a newly formed conduction band at the weakly bound interface, indicating a strong impact of the weak electronic coupling on the wave function connection.