Effect of Structural Fluctuations on Elastic Lifetimes of Adsorbate States: Isonicotinic Acid on Rutile(110)

Abstract

We sample ab-initio molecular dynamics trajectories to address the impact of structural fluctuations on elastic lifetimes of adsorbate states at room temperature focusing on heterogeneous charge injection from isonicotinic acid as a key anchoring unit in dye-sensitized energy devices. Complementing related theoretical studies, we employ a Green's function technique based on density functional theory to account for a fully semi-infinite substrate of rutile TiO 2 (110). We address the effect of a core-excitation enabling direct comparison with soft X-ray experiments. We find that room temperature fluctuations drastically improve the agreement with experimental lifetime measurements while the core-hole plays an important role shifting the spectra and reducing the electron vibrational coupling of the adsorbate states. Ultimately, the emerging resonance spectra highlight the role of the continuum of acceptor states in temperature broadened Voigt-type profiles.

Kinetic Control of Oxygen Interstitial Interaction with TiO2(110) via the Surface Fermi Energy

“…Several methods have been reported to change E F at the surface intentionally. For example, gap states introduced by surface point defects have been predicted by DFT to influence E F strongly, and such effects have been reported experimentally. , Some bulk dopants change the value of E F at the surface, − as can certain adsorbates. − Creation of heterojunction structures between very thin TiO 2 and a different underlying semiconductor with controllable doping enables some control over E F at the TiO 2 surface . Combinations of methods, such as Ar bombardment followed by exposure to an oxygen plasma and annealing, varies E F at the surface over a wide range .…”

Ultrafast Dynamics of Electronic Resonances in Molecules Adsorbed on Metal Surfaces: A Wave Packet Propagation Approach

“…[54][55][56][57][58][59][60][61] Rather simple model descriptions of the system have been used in these early works. It is only recently that RCT between single molecular adsorbates and semiconductor surfaces has been addressed at the ab initio level, 62 however within the stationary Green's function framework that does not admit time-dependent Hamiltonians.…”

Key Role of the Surface Band Structure in Spin-Dependent Interfacial Electron Transfer: Ar/Fe(110) and Ar/Co(0001)

“…Here, we consider k-averaged spectra since we aim at modeling an isolated adsorbate rather than a periodic array of adsorbates. 20,21 The peaks shift up in energy as the adsorbate approaches the surface displaying a linear behavior. We determine the line widths Γ by fitting a Lorentzian…”

“…eq ) of the 4s Ar* resonance for minority (a) and majority spin (c) on Co(0001) as a function of the adsorption height. Here, we consider k -averaged spectra since we aim at modeling an isolated adsorbate rather than a periodic array of adsorbates. , The peaks shift up in energy as the adsorbate approaches the surface displaying a linear behavior. We determine the line widths Γ by fitting a Lorentzian and compare the results for the two spin polarizations in Figure b.…”