Page 262 - Handbook of Instrumental Techniques for Analytical Chemistry
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252 Handbook of Instrumental Techniques for Analytical Chemistry
Figure 15.2 Major vibrational modes for a nonlinear group, CH 2 . (+ indicates motion from the plane of page to-
ward reader; – indicates motion from the plane of page away from reader.) (Reprinted from R. M. Silverstein,
G. C. Bassler, and T. C. Morrill, Spectrometric Identification of Organic Compounds, 4th edition. New York: John
Wiley & Sons, 1981, p. 166, by permission of John Wiley & Sons, Inc., copyright © 1981.)
How It Works
In simple terms, IR spectra are obtained by detecting changes in transmittance (or absorption) intensity
as a function of frequency. Most commercial instruments separate and measure IR radiation using dis-
persive spectrometers or Fourier transform spectrometers.
