Optical absorption spectra of lead iodide nanoclusters

Optical absorption spectra of nanoclusters of lead iodide, synthesized by t he colloidal technique, have been investigated. It is shown that the absorp tion peaks are due to different orders of interband transitions of a nomina lly single size of particles rather than the first-order transitions of a n umber of discrete sizes of particles, as reported earlier. The model used t o explain the spectra of lead iodide has also been used to account for the optical absorption peaks of colloidal mercuric iodide and bismuth tri-iodid e. [S0163-1829(98)01443-X].