ABSTRACT
Sections 5.1 and 5.3). • the characteristics of a π-bond in carbonyl compounds Chapter 5,
Section 5.9; Chapter 15, Sections 15.1-15.3 and 15.5-15.7) • aromaticity and aromatic compounds (Chapter 21, Sections 21.1,
21.7, and 21.8)
This chapter will discuss three methods for structure determination that involve the use of different types of energy. When a molecule is subjected to a high-energy electron beam, fragmentation occurs and the fragments are observed in a technique called mass spectrometry. When a molecule is irradiated with infrared light, the molecule absorbs that energy and it is dissipated via vibrations rather than bond cleavage. That energy is measured as it emerges from the compound being irradiated and recorded. The energy of vibration for a bond depends on the atoms connected to the bond and the strength of that bond. Therefore, infrared spectroscopy is a good method for determining the functional groups within a molecule.
