Basic atomic emission spectroscopy

Figure 1.2 shows the basic instrumentation necessary for each technique. At this stage, we shall define the component where the atoms are produced and viewed as the atom cell. Much of what follows will explain what we mean by this term. In atomic emission spectroscopy, the atoms are excited in the atom cell also, but for atomic absorption and atomic fluorescence spectroscopy, an external light source is used to excite the ground-state atoms. In atomic absorption spectroscopy, the source is viewed directly and the attenuation of radiation measured. In atomic fluorescence spectroscopy, the source is not viewed directly, but the re-emittance of radiation is measured. 

L. Perring and M. Basic-Dvorzak, Determination of Total Tin in Canned Food Using Inductively Coupled Plasma Atomic Emission Spectroscopy, Anal. Bioanal. Chem. 2002,374, 235. 

Perring, L., Basic-Dvorzak, M. Determination of total tin in canned food using inductively coupled plasma atomic emission spectroscopy. Anal. Bioanal. Chem. 374, 235-243 (2002)... 

An introductory manual that explains the basic concepts of chemistry behind scientific analytical techniques and that reviews their application to archaeology. It explains key terminology, outlines the procedures to be followed in order to produce good data, and describes the function of the basic instrumentation required to carry out those procedures. The manual contains chapters on the basic chemistry and physics necessary to understand the techniques used in analytical chemistry, with more detailed chapters on atomic absorption, inductively coupled plasma emission spectroscopy, neutron activation analysis, X-ray fluorescence, electron microscopy, infrared and Raman spectroscopy, and mass spectrometry. Each chapter describes the operation of the instruments, some hints on the practicalities, and a review of the application of the technique to archaeology, including some case studies. With guides to further reading on the topic, it is an essential tool for practitioners, researchers, and advanced students alike. 

The basic design of an atomizer is the same as that for flame emission spectroscopy (Figure 2.35). The method of producing an aerosol involves spraying the sample in air or oxidant gas. The larger drops precipitate on the baffles of the... 

Li or a Li compound in the flame gives a bright crimson color due to its emission of670.8 nm photons produced by the short-lived species LiOH. This is the property that allows for the spectrophotometric determination of Li by atomic absorption spectroscopy (AAS) down to 20 ppb. Inductively-coupled plasma emission spectroscopy (ICPAES), inductively-coupled plasma mass spectroscopy (ICPMS), and ion chromatography (IC) improve this limit to about 0.1 ppb. A spot test for detection of Li down to 2 ppm is provided by basic KIO4 plus FeCl3. 

Inductively Coupled and Microwave Induced Plasma Sources for Mass Spectrometry 4 Industrial Analysis with Vibrational Spectroscopy 5 Ionization Methods in Organic Mass Spectrometry 6 Quantitative Millimetre Wavelength Spectrometry 7 Glow Discharge Optical Emission Spectroscopy A Practical Guide 8 Chemometrics in Analytical Spectroscopy, 2nd Edition 9 Raman Spectroscopy in Archaeology and Art History 10 Basic Chemometric Techniques in Atomic Spectroscopy... 

Describe the basic differences between atomic emission and atomic absorption spectroscopy. 

Part V covers spectroscopic methods of analysis. Basic material on the nature of light and its interaction with matter is presented in Chapter 24. Spectroscopic instruments and their components are described in Chapter 25. The various applications of molecular absorption spectrometric methods are covered in some detail in Chapter 26, while Chapter 27 is concerned with molecular fluorescence spectroscopy. Chapter 28 discusses various atomic spectrometric methods, including atomic mass spectrometry, plasma emission spectrometry, and atomic absorption spectroscopy. 

With the exception of better optical resolution needed, the basic instrument used for atomic emission is very similar to that used for atomic absorption with the difference that no primary light source is used for atomic emission. One of the most critical components for this technique is the atomisation source because it must also provide sufficient energy to excite the atoms as well as atomise them. The earliest energy sources for excitation were simple flames, but these often lacked sufficient thermal energy to be truly effective sources. The development in 1963 and the introduction in 1970 of the first commercial inductively coupled plasma (ICP) as a source for atomic emission dramatically changed the use and the utility of emission spectroscopy (Thompson Walsh 1983). 

The basic instrumentation for atomic-fluorescence spectroscopy is shown in Figure 10.13. The source is placed at right angles to the monochromator so that its radiation (except for scattered radiation) does not enter the monochromator. The source is chopped to produce an AC signal and minimize flame-emission interference. As in molecular fluorescence (Chap. 9), the intensity of atomic fluorescence is directly proportional to the intensity of the light impinging on the sample from the source. 

The early use of a flame as an excitation source for analytical emission spectroscopy dates back to HerscheF and Talbot, who identified alkali metals by flame excitation. The work of Kirchhoff and Bunsen also was basic to the establishment of this technique of atomic excitation. One of the earliest uses of flame excitation was for the determination of sodium in plant ash (1873) by Champion, Pellet, and Grenier.Thus use of the flame paralleled that of arc and spark excitation in the 1800 s. 

In 1955 Walsh established the foundations of modern analytical atomic absorption spectroscopy. In the same year Alkemade and Milatz also published a paper suggesting similar procedures. The work of Walsh, however, was much more detailed, since he examined the theory of the method, the basic principles involved, the instrumentation requirements, and its advantages over flame emission. 

This textbook is an outgrowth of the author s experience in teaching a course, primarily to graduate students in chemistry, that included the subject matter presented in this book. The increasing use and importance of atomic spectroscopy as an analytical tool are quite evident to anyone involved in elemental analysis. A number of books are available that may be considered treatises in the various fields that use atomic spectra for analytical purposes. These include areas such as arc-spark emission spectroscopy, flame emission spectroscopy, and atomic absorption spectroscopy. Other books are available that can be catalogued as methods books. Most of these books serve well the purpose for which they were written but are not well adapted to serve as basic textbooks in their fields. 

Mermet j. M., Spectroscopic diagnostics basic concepts, in Boumans P. W. J. M. (ed) (1987) Inductively coupled plasma emission spectroscopy, Part II, Wiley-Interscience, New York, 353-386. Diermeier R. and Krempl H. (1967) Thermische Anregungsfunktionen und Normtemperaturen von Atom-und lonenlinien in Zweikompon-entenplasmen, Z Phys 200 239-248. 

Spectroscopy is basically an experimental subject and is concerned with the absorption, emission or scattering of electromagnetic radiation by atoms or molecules. As we shall see in Chapter 3, electromagnetic radiation covers a wide wavelength range, from radio waves to y-rays, and the atoms or molecules may be in the gas, liquid or solid phase or, of great importance in surface chemistry, adsorbed on a solid surface. 

Atomic spectroscopy as a means of detection in gas chromatography is becoming popular because it offers the possible selective detection of a variety of metals, organometallic compounds, and selected elements. The basic approaches to GC-atomic spectroscopy detection include plasma emission, atomic absorption, and fluorescence. 

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