6.11: Polyacetylene (alternating bond model)
- Page ID
- 52342
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A more accurate model of polyacetylene includes the effects of alternating single and double carbon-carbon bonds on the polymer backbone. Since double bonds contain a slightly higher electron density than single bonds, they are slightly shorter. Thus, the single-double bond alternation establishes a static deformation with twice the period, \(a_{0}\), of the average bond model for polyacteylene. The periodic charge density established by the deformation is known as a charge density wave. The primitive lattice vector is a \(\bf{\tilde{a_{1}}} = 2a_{0}\bf{\tilde{x}}\).
