Silicon nanoparticles were produced by a relatively low temperature (164 degreesC), solution-phase synthesis. The particles exhibit UV to blue photoluminescence (PL) which varied with excitation wavelength. The average lifetimes, excited at 300 nm, ranged from 4.4 to 5.9 ns. The mean particle diameter, determined by atomic force microscopy, was approximate to1.08 nm. The PL spectra of particles passivated with methoxy or butyl groups were blue-shifted with respect to those passivated with hydroxy groups.