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TN-100 FUNDAMENTAL INFRARED SPECTROSCOPY

by Hue Phan Principle of Infrared Spectroscopy Spectroscopy is the study of the interaction of electromagnetic radiation with a chemicalsubstance. The nature of the interaction depends upon the properties of the substance. When radiation passes through a sample (solid, liquid or gas), certain frequencies of the radiation are absorbed by the molecules of the substance leading to the molecular vibrations. The frequencies of absorbed radiation are unique for each molecule which provide the characteristics of a substance. The electromagnetic spectrum covers an immense range of wavelengths. The infrared regions areclassified as follows:Near Infrared12500 to 4000cm-1(0.8 to 2.5um)Mid Infrared4000 to 200cm-1(2.5 to 50um)Far Infrared200 to 12.5cm-1(50 to 800um) Figure1 . Interaction of radiation with matter.
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