6: Quantum Mechanics in Reactions
- Page ID
- 60548
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Along "reaction paths", orbitals can be connected one-to-one according to their symmetries and energies. This is the origin of the Woodward-Hoffmann rules.
- 6.1: Reduction in Symmetry Along Reaction Paths
- As fragments are brought together to form a larger molecule, the symmetry of the nuclear framework (recall the symmetry of the coulombic potential experienced by electrons depends on the locations of the nuclei) changes. However, in some cases, certain symmetry elements persist throughout the path connecting the fragments and the product molecule. These preserved symmetry elements can be used to label the orbitals throughout the 'reaction'.
- 6.2: Orbital Correlation Diagrams - Origins of the Woodward-Hoffmann Rules
- Connecting the energy-ordered orbitals of reactants to those of products according to symmetry elements that are preserved throughout the reaction produces an orbital correlation diagram.