Talk:Diatomic carbon

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Confusing!![edit]

Quote:"...molecular orbital theory shows that there are two sets of paired electrons in the sigma system (one bonding, one antibonding), and two sets of paired electrons in a degenerate pi bonding set of orbitals. This adds up to give a bond order of 2, meaning that there exists a double bond between the two carbons in a C2 molecule." "This is surprising because the MO diagram of diatomic carbon would show that there are two pi bonds and no sigma bonds." How can Molecular Orbital theory predict that the two pi orbitals are bonding (net order 2) and the sigma bonding and antibonding have no net contribution BUT the MO diagram does not show it? !!! I believe that this can NOT be correct. You just put in the sigma levels, bonding and anti and also put in the pi bonding orbitals. The statement as written can not be correct. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ~π __ __ . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . π ↑↓ ↑↓ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .~σ ↑↓ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . σ ↑↓ MO Theory and Diagram must agree if done correctly, right?216.96.76.60 (talk) 19:58, 17 February 2013 (UTC)

Properties[edit]

Can it exist at room temperature? What is boiling nd melting point? — Preceding unsigned comment added by 79.191.191.243 (talk) 23:20, 23 October 2013 (UTC)

Sure it exists at room temperature. If you read the article, you'll see that due to its autoplymersation, you can't accumulate the bulk substance, and thus cannot find the boiling and melting points experimentally. Plasmic Physics (talk) 23:52, 23 October 2013 (UTC)

Formulaic concern[edit]

In the second row of the article, dicarbon is drawn with a triple bond between the carbon atoms, contrary to double bond of the drawing in the box just on the right, and to what is stated in the text of the article. In addition, as for the molecular orbital description of the same bond, it seems to me incomplete and not clear; perhaps a M.O. diagram could be profitable. Ekisbares (talk) 10:45, 24 November 2014 (UTC)

Although the triplet ground-state is bound by a double bond, the singlet excited-state is apparently very close in energy. The singlet state is chosen to be represented by the formula as it represents the most completely electronically paired state for simplicity. Plasmic Physics (talk) 04:14, 25 November 2014 (UTC)
Thanks for this answer, Plasmic Physics. The reason I came onto the talk page was because I had the same question as Ekisbares. I think something along the lines of your answer given here would be fitting on the main article if placed as a side note or in parentheses, as I can see it being assumed to be a mistake. I'm unsure how to reword to be a bit simpler or perhaps slightly shorter, otherwise I'd have done it myself That kiwi guy (talk) 08:31, 17 January 2015 (UTC)
OK, but I've since changed my mind. In hind sight, it seems like a rather silly reason. Plasmic Physics (talk) 20:22, 17 January 2015 (UTC)