Virtual molecules and virtual spectra: Surface-enhanced Raman scattering for molecules with interactions
Phys. Rev. B 113, 205420 – Published 19 May, 2026
DOI: https://doi.org/10.1103/mdbq-7zl6
Abstract
Surface-enhanced Raman scattering (SERS) has been considered as a powerful trace-level analytical technique for a diversity of fields. However, a molecule in the real world inevitably interacts with other molecules or external stimuli, which often results in obvious changes of its SERS spectrum, e.g., relative intensity, broadening/narrowing, shifting, splitting/merging of the peaks, emergence of new peaks and/or disappearance of existed peaks, etc. These bring fundamental challenges to SERS in solving real-world problems through recognition of the molecule's fingerprints, which has long been an open question in the field. We proposed here a virtual molecules (VMs) and virtual spectra method to deal with the molecule's interactions, and reformulated SERS with two concepts, i.e., cross-section function and relative scattering ability of molecules, which are valid for molecular systems with/without interactions. We established an approach to experimentally obtain the cross-section function and the relative scattering ability of VMs, by which the SERS behavior of molecular systems can be explicitly described by our formulation, with no need to recognize the molecule's fingerprints. These efforts consolidate the foundation of SERS, and push forward its applications as a powerful trace-level analytical technique in solving real-world problems.
