A simple GUI for modeling the optical properties of single metal nanoparticles

We present a graphical user interface, based on the modified long-wavelength approximation, to compute the optical properties of single metal nanoparticles of ellipsoidal geometry (spheres, rods, and disks). The user-friendly interface allows one to readily gauge the accuracy of results obtained using the modified long-wavelength approximation. For spherical particles, up to 10-nm diameter, we confirm that our approach yields an exact correspondence with Mie theory, and gives an approximation error of less than 15% for gold (silver) particles with diameters approaching 40 nm (26 nm). Results are shown to be sensitive to the source data for the optical constants for a given material. The modular nature of the simulation platform provides a quick and intuitive guide for optical characterization experiments.