RT Journal Article
T1 Voltage tuning of photoinduced charge transfer resonances between 2,2′-bipyridine and a nanostructured silver electrode.
A1 Valdivia Mantas, Samuel
A1 Aranda, Daniel
A1 Otero-Fernández-de-Molina, Juan Carlos
A1 López-Tocón, Isabel
K1 Química física
K1 Efecto Raman de superficie intensificada
K1 Química de superficies
K1 Transferencia de carga
K1 Electrodos
AB The effect of applied electric potentials and excitation wavelengths (785, 532, 473 nm) on the Surface-Enhanced Raman scattering (SERS) of 2,2′-bipyridine (2,2′-bpy) adsorbed on a silver electrode has been analyzed on the basis of a charge transfer (CT) resonance mechanism. DFT/TD-DFT calculations performed for a simple model of surface complex (Ag2-2,2′-bpy) point out that 2,2′-bpy preferably adsorbs through both nitrogen atoms in a cis-conformation with edge-on orientation. The calculated spectra in resonance with the two first bright metal-to-molecule charge transfer electronic states (CT0;B1 and CT1;B1) account for the main experimental features: the selective enhancement of the totally symmetric modes recorded at about 1585, 1560 and 1480 cm−1 under 532 nm line, staying the 1560 cm−1 band as the most intense under 473 nm line at more negative electrode potential. The split of SERS bands recorded in the 1600, 1000 and 600 cm−1 regions point to the existence of a monodentate coordination of the cis-conformer. The calculated resonance condition up to CT0 and CT1 states is fulfilled under 532 and 488 nm excitation lines, respectively, agreeing with the behaviour of the intensity-potential profile of the bands for each excitation wavelength.
YR 2023
FD 2023-11-17
LK https://hdl.handle.net/10630/28841
UL https://hdl.handle.net/10630/28841
LA eng
NO Samuel Valdivia, Daniel Aranda, Juan Carlos Otero, Isabel López-Tocón, Voltage tuning of photoinduced charge transfer resonances between 2,2′-bipyridine and a nanostructured silver electrode, Applied Surface Science, Volume 646, 2024, 158871, ISSN 0169-4332, https://doi.org/10.1016/j.apsusc.2023.158871
NO Funding for open Access charge: Universidad de Málaga / CBUA.This research has been supported by Junta de Andalucía/FEDER(UMA18-FEDERJA-049 and P18-RT-4592
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 20 ene 2026