ELECTRONIC AND OPTICAL PROPERTIES OF M13 AND M12Cr (M = Cu, Ag, and Au) CLUSTERS: A COMPARATIVE DFT INVESTIGATION

Tóm tắt

Nanoclusters have recently emerged as promising building blocks with potential applications in advanced nanostructured materials, owing to their unique catalytic, magnetic, and electronic properties. This work compared the infrared spectra and absorption spectra of the ground-state structures M₁₃ and M₁₂Cr (M = Cu, Ag, and Au) clusters using density functional theory and time-dependent density functional theory approaches. Specifically, we employed the BP86 functional combined with cc-pVTZ-pp and cc-pVTZ basis sets for M and Cr atoms, respectively. Chromium (Cr) dopant atom has five unpaired valence electrons, with an outermost shell configuration of 3d⁵4s¹. These valence electrons exhibit high mobility, allowing them to move freely and form a delocalized electron cloud for clusters. In contrast, the remaining electrons that do not participate in forming the delocalized electron cloud localize in the d-Cr, resulting in significant differences in the characteristics of IR vibrational modes for M₁₃ and M₁₂Cr clusters. The absorption spectra analysis revealed no absorption signals for Ag₁₂Cr and Cu₁₂Cr clusters, while Au₁₂Cr cluster exhibits a notable absorption peak at 1270 nm (0.976 eV). These findings provide valuable insights into the vibrational and optical characteristics, establishing a foundation for further theoretical and experimental investigations.