What Is Molecular Spectroscopy

The study of the frequencies of electromagnetic radiation that are absorbed or emitted by substances and the correlation between these frequencies and specific types of molecular structure. [Pg.364]

Organic molecules are flexible structures. They rotate in solution, their bonds stretch, bend, and rotate, and they contain electrons that can move from one electronic energy level to another. We know from experimental observations and from theories of molecular structure that all energy changes within a molecule are quantized that is, they are subdivided into small, but well-defined, increments. For example, vibrations of bonds within molecules can undergo transitions only between allowed vibrational energy levels. [Pg.364]

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