Molecules with an extended π system well described by resonance hybrid

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The discussion centers on the concept of extended π systems in chemistry, particularly in relation to linear polyenes and polyaromatic compounds. An extended π system refers to a molecular structure where π electrons are delocalized over multiple adjacent atoms, allowing for resonance stabilization. Examples of linear polyenes include compounds like butadiene and octatetraene, while polyaromatic compounds include structures such as naphthalene and anthracene. The conversation highlights the importance of resonance in these systems, illustrating how individual rings in polyaromatic compounds can share π electrons, contributing to the overall stability and delocalization of the electron cloud. The mention of honeycomb images serves as a metaphor for understanding the interconnectedness of these π systems in polyaromatic compounds.
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Homework Statement:: [...] Molecules with an extended π system such as linear polyenes and polyaromatic compounds are well described by resonance hybrids as well as by delocalized orbitals in molecular orbital theory.
Relevant Equations:: N/A

This is not a Homework question. I was reading Resonance (chemistry) from Wikipedia. I am not able to understand this sentence, "Molecules with an extended π system such as linear polyenes and polyaromatic compounds are well described by resonance hybrids as well as by delocalized orbitals in molecular orbital theory "

What is an extended π system? Given examples of linear polyenes and polyaromatic compounds of extended π system, when I searched polyaromatic, I found bee honeycomb images.
Hexabenzocoronene.svg.png


[Moderator's note: moved from a homework forum.]
 
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You see a honeycomb, I see a system where each individual ring - thanks to the resonance - has a π system. They do combine meaning the system is extended.

For some rings it is immediately obvious, for some it requires spotting that - while the double bond is drawn as if it was on the other side - it is technically shared by two rings, for some it requires drawing a resonance structure. But it is all there.
 
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