Theoretical investigations of noble metal nanoparticles are important for determining the origins of the unique chemical and physical properties of these systems that lead to applications in photonics, sensing, catalysis, etc. Using DFT and TDDFT calculations, we have recently elucidated the optical absorption and photoluminescence spectra of Au25(SR)18-and related nanoparticles. Significant changes in the geometric and electronic structure of this system are observed upon photoexcitation. Electron dynamics within these systems are investigated in order to understand the dynamics of hot carriers (electrons and holes) that underlie their potential applications in solar energy and photocatalysis.
Small silver clusters encapsulated by DNA have been of interest for biotagging applications because they display fluorescence. The absorption and CD spectra of helical silver nanowires are computed and compared with experimental spectra. The agreement between theory and experiment suggests that the silver-DNA clusters have a helical arrangement.