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Chemistry

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    $\begingroup$ Hückel's simplistic rule arrives at the same result in a fraction of the time. $\endgroup$
    – KarlsMaranjs
    Commented Dec 21, 2022 at 4:20
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    $\begingroup$ @KarlsMaranjs ..... but as pointed out in the answer you just replied to, Hückel's rule is hardly a foolproof method. It has arrived at the right conclusion purely by chance. If I came up with a "rule" that said "all molecules are aromatic", it would also arrive at the same (correct) conclusion in an even shorter time, but you surely wouldn't think it sensible to use such a rule. $\endgroup$
    – orthocresol
    Commented Dec 21, 2022 at 18:02
  • $\begingroup$ @orthocresol by chance? Hückel’s rule is derived from the MOT. A huge portion of theoretical chemistry was developed based on this theory, that you just called chance. Still, it’s not the only criteria to meet to determine if a molecule is aromatic. Of course every rule comes with exceptions, but in most cases if all 4 criteria are met then the molecule is almost certainly aromatic. Even for this one which is a very particular case, with the right analysis you have the right answer. And yes, exp methods are always the way to go, but without extra information Hückel is your best ally here. $\endgroup$
    – KarlsMaranjs
    Commented Dec 21, 2022 at 18:27
  • $\begingroup$ @KarlsMaranjs Huckel's 4n+2 rule is a single, highly simplified, rule-of-thumb obtained from the generalisation of MO theory to monocyclic compounds. It does not have the same fundamental importance that MO theory itself has, so the wider application of MO theory within chemistry that you cite is not relevant. For the rest of your comment, I have nothing to say except what I already said, so I won't repeat myself - e.g. "with the right analysis you get the right answer" - I can claim the same about my obviously-false rule. I am not saying that Huckel is false, btw, just too simplified. $\endgroup$
    – orthocresol
    Commented Dec 21, 2022 at 19:32