Talk:Dangling bond

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Dangling bond is one of widely used term in the chemistry and physics but still is not defined uniquely. Due to this reason I would like to put my point of view to discuss it and to define this term ‘Dangling bond’ more precisely and to determine the range for utilization. Very often the dangling bond occurs when an atom is missing a neighbor to which it would be able to bind. But this defenition can be used for ideal crystals when the atom position is well-defined and cannot be used for amorphous solids when the atom position for neighbour atom may not defined. As result, the term of dangling bond is used for amorphous states when the same atoms have the different coordination numbers. But, from quantum chemical and, more widely, from chemical point of view the dangling bond does not exist. Let us look for the simple chemical reaction for ethane dehydrogenation:

      H H
      | |            . .            H      H
1)  H-C—C-H    =>  H-C-C-H + H2  =>   >C=C<
      | |            | |            H      H
      H H            H H

    H     H        . .
2)   >C=C<   =>  H-C=C-H + H2  =>   H-C≡C-H
    H     H

3)  H-C≡C-H  =>  .C≡C. + H2   => C2

Every dehydrogenation step may be interpreted as two dangling bonds formation, but from the chemical point of view there is an ordinary chemical reaction with decreasing of coordination number of every carbon atoms. This process of coordination number changing is accompanied by electron configuration of carbon atoms. Chemical activity for every molecule increasing during decreasing of the hydrogen content and no dangling bond formation can be observed. From the quantum chemical point of view all these processes may be defined as electron rearrangement around carbon atom. The same phenomenon may be observed for any other cases, for which the ‘dangling bond’ conception were used. But the question “What is mean the ‘dangling bond’?” is still opened. If you have an your own point of view, please, show it and we will discuss the problem. — Preceding unsigned comment added by (talkcontribs) November 2005‎

Just wrong, proven by the now well-written and referenced article. --Rainald62 (talk) 13:28, 22 January 2015 (UTC)

article is poorly organised. someone please help structure it better. — Preceding unsigned comment added by Anonymi (talkcontribs) May 2006‎

Also outdated. --Rainald62 (talk) 13:28, 22 January 2015 (UTC)


I changed the rating of the article from "Start class" to "B class". Imho, the only weak point is the references: too many, too focused on a-Si. --Rainald62 (talk) 13:28, 22 January 2015 (UTC)