Microstructure of nanocrystalline PbS powders and films

Nanocrystalline PbS powders and nanostructured PbS films have been produced by different deposition procedures. According to scanning and transmission electron microscopy results, the average size of PbS particles in the nanopowders is 8 to 20 nm, and the average grain size in the nanofilms is 40 to 80 nm. As shown by electron diffraction, the nanocrystalline PbS powders have the B1 structure (sp. gr. \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$Fm\bar 3m$$\end{document}).