Our serie of Scientific Seminars continues with the next talk: 

Title: Seeing Molecules with Light: Tip-Enhanced Spectromicroscopies at the Atomic Scale

Author: Pablo Merino, Interdisciplinary studies based on nanoscopic systems (ESISNA) group, ICMM-CSIC

Where: Sala de Seminarios, ICMM-CSIC

When: 15th October, 12h

Abstract: Tip-enhanced spectromicroscopies combine the chemical and photophysical sensitivity of optical spectroscopy with the spatial resolution of scanning probe microscopy, providing access to light–matter interactions at the scale of individual molecules. In this talk, I will introduce the principles of tip-enhanced Raman scattering (TERS) and related tip-enhanced spectroscopies, focusing on how atomic-scale control of the tip–molecule junction can transform a scanning probe microscope into a nanoscale optical laboratory. I will discuss how these techniques can be used not only to identify molecular species through their vibrational fingerprints, but also to visualize molecular excitations, electronic and spin states, and their coupling to the local environment. Examples will include hyperspectral TERS imaging of individual molecules,[1] where adsorption-induced symmetry breaking and sub-ångstrom structural distortions are revealed through changes in vibrational spectra and their spatial distribution; resonant TERS of a single-molecule Kondo system,[2] illustrating the interplay between molecular charge, spin and vibrational degrees of freedom; and tip-enhanced electroluminiscence of coupled molecular assemblies,[3] where spatially resolved optical spectroscopy provides direct access to delocalized and entangled excitonic states. Together, these examples illustrate how tip-enhanced spectromicroscopies can bridge structural, vibrational, electronic and optical information, opening a route towards controlling light–matter interactions with atomic precision.

[1] de Campos Ferreira et al. Journal of the American Chemical Society, 148, 9375–9381 (2026). 

[2] de Campos Ferreira et al. ACS Nano, 18, 13164–13170 (2024). 

[3] Doležal et al. ACS Nano, 16, 1082–1088 (2022).