Metal Nanoparticle Synthesis & Plasmon Resonance

This simulator models the wet-chemical synthesis of gold nanoparticles in 3D. A reducing agent is injected into a solution of Au³⁺ ions; as it diffuses through the flask, ion concentration climbs until it crosses a critical supersaturation threshold and fires a burst of nucleation (the LaMer mechanism), after which the surviving ions diffuse onto the existing nuclei and grow them rather than form new ones. Particle size sets the wavelength of the surface plasmon resonance, so the solution's color and its live absorption spectrum shift from red toward blue/purple as the nanoparticles coarsen. Adjust reducing agent concentration and temperature to see how each reshapes the nucleation burst and the final particle size distribution.