Formation of Ultrafine Particles by Gas-Evaporation Technique. V. Silicon and Germanium in Argon

Abstract

Fine particles of silicon and germanium were prepared by evaporation in argon gas at low pressures, and they were studied by electron microscopy. Relatively large particles showed distinct crystal habits for both materials. A typical habit of silicon was an polyhedron bounded by twenty four {311} and eight {111} faces, and that of germanium, an icositetrahedron bounded by {311} faces. Crystallites with these habits have the diamond structure as usual. However, relatively small germanium particles, which were formed in the inner part of the smoke, showed no distinct habit and had an unknown structure with a tetragonal unit cell, a=5.37 Å and c=9.04 Å.