Photothermal Spectroscopy Methods for Chemical Analysis

Book excerpt: A unique guide to the application and theory of photothermalspectroscopy. This book debunks the myth that photothermal spectroscopy is toocomplicated for practical application to chemical analysis, anddemonstrates the advantages this technique has over conventionalspectroscopy in facilitating extremely sensitive measurements ofoptical absorption in homogeneous media. The book covers thesubject from the ground up, lists all practical considerationsneeded to obtain accurate results, and provides a working knowledgeof the various methods in use--including photo acoustics andphotopyroelectric techniques. Bringing together a wealth of information that has been scatteredthroughout the professional literature, Photothermal SpectroscopyMethods for Chemical Analysis covers methods and information thatshould be known to every analytical chemist, including: * Descriptions of photothermal spectroscopy using a consistentmathematical language * Helpful examples from the literature of analytical applicationsand current research * Illustrations of all important points, consistent equations, andnumerous original figures * A discussion of laser technology and how it is used to obtainaccurate results from extremely small samples of a few molecules * Everything spectroscopists need to know to construct their ownapparatus and use it to conduct successful experiments * Tips on how to interpret experimental results effectively whenusing nonlinear processes and in many other situations inphotothermal spectroscopy * Considerations for further study of heterogeneous sampleanalysis * Unified nomenclature of the patchwork of terms used byresearchers in analytical and physical chemistry, physics, andoptical engineering * Equations that are derived with the aid of a symbolic languageprocessor to ensure correct results Photothermal spectroscopy has seen major advances since the adventof laser technology twenty-five years ago. It is now possible,using a laser's coherent and powerful output, to obtain extremelysensitive measurements of optical absorption that exceed those ofmass spectroscopy by two or three times, and produce accurateresults from only a few molecules. Focusing on samples in homogeneous media, this book provides aunique guide--incorporating theory and application--to allavailable photothermal spectroscopy techniques for chemical andmaterial analysis. It uses a systematic approach in itscomprehensive treatment of the theory, and covers all the necessarybackground material, from laser optics to fluid dynamics. This accessible text describes the various processes used to detectthermal perturbation of a sample, ranging from optical excitationto nonlinear processes, and covers all optical principles necessaryto understand photothermal spectroscopy. When dealing withhydrodynamic equations that govern energy transfer in the samplematrix, it provides an original impulse-response approach. Inaddition, the book explains how to construct the apparatus oneneeds to conduct successful photothermal experiments, sincecommercial equipment is not available as in conventionalspectrophotometry. Throughout, this book draws on information from a wide range offields, including analytical spectroscopy, measurement physics,physical optics, and chemical dynamics. Providing clearexplanations at every turn, the author demonstrates a completeunderstanding of the theory and applications as a firm basis forthe correct interpretation of experimental results. For analytical chemists, as well as for students at the graduatelevel, Photothermal Spectroscopy Methods for Chemical Analysis isan unmatched resource that develops a consistent mathematical basisfor signal description, consolidates previous theories, andprovides invaluable insight into laser technology.