Classification of emission lines of the Group IIIB elements, aluminium, gallium and indium, excited by Grimm glow discharge plasmas using several different plasma gases

Abstract

In order to clarify the spectroscopic characteristics of the Group IIIB elements in Grimm glow discharge plasmas, the relative intensities of their emission lines in the wavelength range 160–800 nm were investigated and tabulated when using different plasma gases, viz., argon, neon, argon–helium and neon–helium. It was characteristic of the glow discharge light source that the emission spectra observed were strongly dependent on the type of plasma gas employed. Extremely intense ionic lines were observed when neon rather than argon was employed as the plasma gas. Furthermore, different groups of ionic lines could be observed only in the helium-containing plasmas. The excitation of these ionic lines can be principally attributed to charge-transfer collisions between the analyte atoms and the plasma gas ions.