Author:

Keywords:

Science & Technology, Physical Sciences, Chemistry, Physical, Chemistry

Abstract:

A study is described of the interactions occurring when a solid is introduced into the afterglow of various microwave-induced plasmas. As a major result of these interactions, metal atoms are ejected from the solid phase at surface temperatures below 800 K and brought into the gas phase where they are measured by the atomic absorption technique. Metal atoms in the gas phase were obtained in a concentration range between 1 × 1010 and 1 × 1012 atoms cm-3. The influence of various parameters on the atomic absorption has been checked: e.g., the chemical composition of the afterglow, the temperature of the solid, the distance between the solid and the plasma, and the nature of a large number of solids. It was found that hydrogen, oxygen, and nitrogen atoms in their ground states are the ultimate reaction partners, which, in a heterogeneous interaction with the solid, lead to the formation of metal atoms in the gas phase. The relative efficiency for this "lattice atomization" process can be qualitatively classified as H > O or N. A mechanism and possible factors determining this trend are briefly discussed. © 1982 American Chemical Society.