Asymmetries in the Electronic Properties of Spheroidal Metallic Nanoparticles, Revealed by Conduction Electron Spin Resonance and Surface Plasmon Resonance

Using electron spin resonance spectroscopy, we demonstrate that the morphological asymmetries present in small spheroidal metallic nanoparticles give rise to asymmetries in the behavior of electrons held in states near the metal's Fermi energy. We find that the effects of morphological asymmetries for these spheroidal systems are more important than the effects of size distributions when explaining the asymmetry in electronic behavior. This is found to be true for all the particles examined, which were made from Cu, Ag, Pd, Ir, Pt, and Au, bearing dodecanethiolate ligands. In the case of the Ag particles, we also demonstrate that the same model used to account for morphological effects in the electron spin resonance spectra can be used to account for small asymmetries present in the plasmon spectrum. This result demonstrates that the electronic properties of even small particles are tunable via morphological changes.

Automated summary

Using electron spin resonance spectroscopy, it has been demonstrated that morphological asymmetries in small spheroidal metallic nanoparticles significantly affect the electronic behavior of states near the metal's Fermi energy. The study found that morphological effects were more important than size distributions in explaining the asymmetry in electronic behavior, and this was consistent across various particles made from different metals. Additionally, the study also showed that morphological changes can tune the electronic properties of even small particles, as evidenced by the modeling used to explain asymmetries in both electron spin resonance spectra and plasmon spectra.