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I have IR spectra of polystyrene with characteristic peaks at 1450cm-1. 1500cm-1 and 1600cm-1. What chemical bond is associated with 1600cm-1 and 1500cm-1?

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As shown here (Figure 2), the lines at 1600 and 1492 (~1500) cm$^{-1}$ correspond to aromatic ring modes.

From my doctoral dissertation (Classical and Quantum Dynamics of Vibrational Energy Flow in Benzene: the CH($\nu = 2$) Overtone. Minehardt, T. J. The University of Texas at Austin. May, 1999): the specific modes correspond to E$_{1u}$ (CC stretch and in-plane CH wag) at 1494 cm$^{-1}$; and E$_{2g}$ (CC stretch, CCC bend, and in-plane CH wag) at 1607 cm$^{-1}$.

Thus, the corresponding bonds are carbon-carbon (stretch), carbon-carbon-carbon (bend), and carbon-carbon-hydrogen (in-plane wag).

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