Chapter 8 Atomic spectroscopy

Abstract

Publisher Summary Elemental analysis at the trace or ultratrace level can be performed by a number of analytical techniques; however, atomic spectroscopy remains the most popular approach. Atomic spectroscopy can be subdivided into three fields that differ by the mode of excitation and the method of measurement of the atom concentrations: atomic emission spectroscopy (AES), atomic absorption spectroscopy (AAS), and atomic fluorescence spectroscopy (AFS). The selection of the atomic-spectroscopic technique to be used for a particular application should be based on the desired result because each technique involves different measurement approaches. AES excites ground-state atoms and then quantifies the concentrations of excited-state atoms by monitoring their radiative deactivation. AAS measures the concentrations of ground-state atoms by quantifying the absorption of spectral radiation that corresponds to allowed transitions from the ground to excited states. AFS determines the concentrations of ground-state atoms by quantifying the radiative deactivation of atoms that have been excited by the absorption of discrete spectral radiation. All of these approaches are discussed in this chapter. AAS with a flame as the atom reservoir and AES with inductively coupled plasma have been used successfully to speciate various ultratrace elements.