Talk:Hückel's rule

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[edit] What is "n"?

what does 'n' represent in this equation?

Here's an example: for benzene, the ring has 6 carbons, so n = 1. That's because 4(1) + 2 = 6. HTH. --HappyCamper 21:58, 11 March 2007 (UTC)

I was about to ask the same question.. what exactly does "n" stand for? HappyCamper's explanation, "Six carbons, so n=1" doesn't clarify much. —Preceding unsigned comment added by 131.247.152.4 (talk) 08:09, 29 November 2007 (UTC)

The article states "n is zero or any positive integer". DMacks (talk) 14:17, 29 November 2007 (UTC)

The value of n is independent of the organic molecule being examined. Lets look at benzene. Benzene has 6 pi electrons correct? Since there are 6 pi electrons, it follows huckel's rule because when n=1 you obtain a value of six. If a different molecule has 8 pi electrons (4 conjugated double bonds), it will not follow huckel's rule no matter what integer you designate n to be. Therefore, molecules such as Cyclooctatetraene (C₈H₈) are not aromatic, but since they are conjugated they are considered to exhibit Antiaromaticity. Basically Huckel's rule states that any conjugated system with 2, 6, 10, 14...(etc) pi electrons is aromatic. —Preceding unsigned comment added by 199.184.238.211 (talk)

Nit-pick: if cyclooctatetraene were planar it would be conjugated and antiaromatic. DMacks (talk) 17:53, 24 April 2008 (UTC)

I believe the rule includes non-binding electrons as well as pi bonded electrons too, anyone want to verify this and change it? —Preceding unsigned comment added by 75.45.1.131 (talk) 03:46, 25 May 2008 (UTC)

If they are involved in resonance, then they aren't "non-bonding". When the resonance-structures are drawn, they actually are pi electrons because they participate in pi-bonds (remember, individual resonance structures do not actually exist). So as a direct answer, electrons drawn as lone-pairs certainly can be involved in resonance and if they are, they are included in the 4n+2 electron count. Hopefully there's information on the aromaticity page about the inclusion/exclusion of various electrons in the aromatic system. DMacks (talk) 05:56, 3 June 2008 (UTC)

[edit] Should fullerenes be discussed in this article?

I think the section on fullerenes at the end should be moved to a different article. Huckel never said anything about fullerenes, so they don't follow any kind of "Huckel's rule". Anyone wish to comment? Shalom (Hello • Peace) 02:15, 9 October 2007 (UTC)