First-principles isomer-specific absorption spectra of Ag-11

The atomic structures, static polarizabilities, and optical absorption spectra of eight low-energy isomers of Ag-11 are investigated from first principles within static and time-dependent density functional theory. The energies of all eight fall within a range of similar to 0.3 eV in width. It is the spectrum of the lowest-energy isomer that exhibits the best overall agreement with the available measured spectra. The analysis indicates that the d electrons play an important role in the optical excitations of Ag-11; the degree of their contribution to the spectra is larger than that found in smaller silver clusters.