Exploring ultra-fast charge transfer and vibronic coupling with N 1s RIXS maps of an aromatic molecule coupled to a semiconductor

Abstract

A note on versions:The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription.For more information, please contact eprints@nottingham.ac.uk FranceWe present for the first time two-dimensional resonant inelastic x-ray scattering (RIXS) maps of multilayer and monolayer biisonicotinic acid adsorbed on the rutile TiO 2 (110) single crystal surface. This enables the elastic channel to be followed over the lowest unoccupied molecular orbitals resonantly excited at the N 1s absorption edge. The data also reveals ultra-fast intramolecular vibronic coupling, particularly during excitation into the LUMO-derived resonance. Both elastic scattering and the vibronic coupling loss features are expected to contain the channel in which the originally excited electron is directly involved in the core-hole decay process. This allows RIXS data for a molecule coupled to a wide bandgap semiconductor to be considered in the same way as the core-hole clock implementation of resonant photoemission spectroscopy (RPES). However, contrary to RPES measurements, we find no evidence for depletion of the participator channel under the conditions of ultrafast charge transfer from the molecule to the substrate densities of states, on the timescale of the core-hole lifetime. These results suggest that the radiative core-hole decay processes in RIXS are not significantly modified by charge transfer on the femtosecond timescale in this system. a) Electronic mail: J.Oshea@nottingham.ac.uk

Role of Dopants on the Local Electronic Structure of Polymeric Carbon Nitride Photocatalysts

“…It is noteworthy that vibronic coupling was previously evidenced by RIXS at the N K‐edge in aqueous ammonia, [ 44 ] spin‐liquid insulator, [ 22 ] and on small organic molecules with other vibrational modes. [ 45,46 ] Our work demonstrates that RIXS can also be used to probe vibronic interactions in polymeric material.…”

Electronic Structure of Aqueous [Co(bpy)3]2+/3+ Electron Mediators

“…To both the high-and the low-energy sides, all RIXS spectra exhibit long tails. We also note that the small signals at slightly lower energies of the elastic peaks (red arrows in RIXS maps) are due to vibronic excitations, 44,45 which are however not resolved here. The two intense emission channels (pink lines) can be attributed to emissions from ligand 2p → N 1s transitions.…”

Resonant inelastic X-ray scattering of a Ru photosensitizer: Insights from individual ligands to the electronic structure of the complete molecule

“…This feature is therefore attributed to vibronic coupling. 28 The main feature of the inelastic scattering at resonance A is the strong enhancement of feature I at an emission energy of 393.6 eV. This is attributed to radiative decay from the highest occupied molecular orbital (HOMO).…”

“…3(b). These data have been published previously 28 but is reproduced here in the same format as the powder data for direct comparison. Many spectral features are similar: the emission spectra on resonance A have features I, II, and III appearing at the same energies and both have the same 0.5 eV shift between the HOMO enhancement at the A and C resonances.…”