Transmission Spectra of Diluted and Concentrated Magnetite Colloids in Liquid Dielectrics

Abstract

Transmission spectra of colloidal solutions of magnetite nanoparticles in kerosene with various volume concentrations of the solid phase and the influence on them of an external magnetic field have been studied. A pronounced maximum in the near-IR region at 740–760 nm appeared in the spectra as the magnetite concentration increased. The magnetite concentration limits at which the transmission spectra were successfully described by the Bouguer–Lambert law were established. The appearance of a maximum in the transmission spectra with increasing concentration was shown to be associated with a minimum in the spectrum of the imaginary part of the refractive index of nanosized magnetite.