A more precise description of electron delocalization volume in mixed materials requires the partition of electron density as done in Bader volume calculations. Here, we define the inclusion volume as the summed Bader volumes of the inclusion atoms, calculated using the Henkelman Group code. This total volume envelopes the full inclusion [see Fig. In panel (b), quantum dynamics-calculated permittivities are plotted using red diamonds and black triangles against the atomic and volume loading percent of silver, respectively. FEMcalculated effective permittivities are shown for different inclusion/matrix permittivity ratios. studies have shown the static polarizability α of silver and gold nanoparticles to be directly proportional to the electron delocalization volume. These analyses considered particles with up to several hundred atoms, and they are applicable to particles that include those with discrete energy levels. To confirm that this trend also holds for the responses considered in our study, we examined the polarizabilities of thirteen silver particles containing from four to 55 atoms, using the process described in Sec. to that of metallic spheres. For a sphere of radius r, α is also directly proportional to its volume: