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2.1.5 Spectroscopy

By using a spectrometer to measure the absorption of IR radiation, we measure the energies absorbed. The energies absorbed are the transitions the molecule can undergo, which relate to the modes themselves. In principle, this is in turn related to the atomic arrangement and chemical interactions that comprise the molecule. To relate to Section 2.1.4, carbon dioxide absorbs IR radiation at three frequencies, each corresponding to the fundamental frequencies of the three IR active vibrational modes.

John S. Riley, DSB Scientific Consulting