Comment on "Multimodal coupling of optical transitions and plasmonic oscillations in rhodamine B modified gold nanoparticles" by M. Stobiecka and M. Hepel, Phys. Chem. Chem. Phys. 2011, 13, 1131.
An article recently published in this journal claimed that a resonance enhanced light scattering (RELS) peak for 22 nm gold nanoparticles was observed at 653 nm, which was about 130 nm higher than the surface plasmon resonance maximum. They also claimed to observe RELS from dilute solutions of Rhodamine B, under conditions where it is expected to be in its monomeric form. This comment shows that the position of the RELS peak for the gold nanoparticles is an artefact of measurement and the RELS from Rhodamine B is simply fluorescence. These findings are likely to have a significant impact on the interpretation of the results in terms of interactions of dyes with gold nanoparticles as well as aggregation of gold nanoparticles, which has been reported elsewhere by the same authors.