TABLE OF CONTENTS Atomic spectroscopy includes all analytical techniques that employ the emission and/or absorption of electromagnetic radiation by individual atoms. There are three kinds of emission spectra:
Continuous spectra, which are emitted by incandescent solids
Line spectra, which are characteristic of atoms that have been excited and are emitting their excess energy
Band spectra, which are emitted by excited molecules
The specific wavelength of the radiation (emitted or absorbed) identifies the element. The intensity of emitted (or absorbed) radiation at the specific wavelength is proportional to the amount of the element present.
Sections 8.2, 8.3, and 8.5 discuss methods that use combustion flames. A nonflame method, electrothermal atomic-absorption spectrometry, is discussed in Sec. 8.3.3. Three techniques can be used to observe the atomic vapor that is produced when a sample solution is nebulized and passed into a flame. These are atomic-absorption spectrometry (AAS), flame emission spectrometry (FES), and atomic fluorescence spectrometry (AFS). Of these, AAS and FES are the most widely used.
Atomic-emission spectroscopy and spectrometry use either electrical discharges or plasmas (Sec. 8.4) for excitation of emission spectra.
Flame spectrometric methods, qualitative and quantitative, can be applied to clinical materials (serum, plasma, and biological fluids), soils, plant materials, plant nutrients, and samples of inorganic and organic substances.
A premixed, laminar-flow flame with well-defined zones has lower background emission and less noise as a result of optical turbulence than a corresponding diffusion flame (total consumption atomizer burner) where the zones are intermixed. Characteristics...
