Theory of the vibrational spectroscopy of polymers, structure-spectrum relationships

The above figures describe the structures and the displacement vectors of an important normal mode of two polymers, (a) trans-PA and (b) cis-PA.  This mode cannot be properly described by traditional methods. This mode is essential because it provides structural information on the bond distances that is otherwise not obtainable for polymeric materials. In turn, these data help understand the structure and the closely related bandgap helping designing systems with desired bandgap values.

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