The optical properties of metallic spherical nanoparticles embedded in host liquid matrix are
studied. Extended Maxwell-Garnett-Mie formulation which accounts for size dispersion, the
intrinsic confinement, and extrinsic size effect, is proposed for the calculation of the effective
dielectric function and absorption coefficient of size dispersion of colloidal solution of Au and
Ag nanoparticles in water. We demonstrate that the size distribution induces an
inhomogeneous broadening and an increase of the amplitude of the plasmon band. A large …