Consider the structure of your cyanine dye. Draw all the

Last updated: 8/9/2022

Consider the structure of your cyanine dye. Draw all the resonance structures that contribute to the conjugation of the central chain (the atoms from one nitrogen atom to the other, inclusive) that we are considering to constitute a one-dimensional box, even those that contribute only slightly. Show that the terminal six-membered rings are not strongly conjugated to the central chain by observing that (i) conjugation in the central chain is independent of conjugation in the terminal rings; and (ii) resonance structures conjugating the terminal rings to the central chain do not keep the rings fully aromatic. Dye used: 1,1' Diethyl-2,2' carbocyanine Iodide (D2CI)