GRAIN-SIZE EFFECT ON THE SPECTRAL CHARACTERISTICS OF CV USING PHOTOACOUSTIC-SPECTROSCOPY

Photoacoustic spectroscopy (PAS) offers a unique method to measure opt ical absorption of materials in the powder form. In this work we emplo y PAS to study the change in the peak absorption of the dye crystal vi olet (CV) in the powder form, as a function of the grain size which wa s carefully controlled. It is observed that as the grain size is compa rable to the incident radiation wavelength, there is an increase in th e blue shift with decreasing the grain size.