Observation of a phase transition in an electrodynamically levitated NH4NO3 microparticle by Mie and Raman scattering

The observation of a phase transition from a solid microparticle into a liq uid droplet of a single levitated NH4NO3 particle using an electrodynamic b alance for particle levitation combined with Raman and Mie spectrospcopy is reported. The phase transition from the solid to the dissolved NH4NO3 can be followed by characteristic changes in the spectral location of Raman sig nals and by a characteristic decrease in the refractive index and an increa se in the particle radius, which is deduced from Mie scattering data. Copyr ight (C) 2000 John Wiley & Sonls, Ltd.