Talk:Bond order

I changed the plus sign in the equation to a minus sign. I am uncertain about this, but I believe this change ensures that the bond order for a single bond is 1 (Rij = dij). ~ mirfakhr Corrected the order of distance terms, now gives sensible values s>1 for double and triple bonds, that are shorted than single bonds. Ouji-fin (talk) 14:00, 3 November 2011 (UTC)

Amide bond order 1.2

Carbon–nitrogen bond has a table of nitrogen groups which says amides have C-N bond order 1.2 - Could this article somehow explain the 1.2. It says " bond orders of 1.1, for example, can arise under complex scenarios and essentially refer to bond strength relative to bonds with order 1." ? - Rod57 (talk) 13:09, 9 April 2016 (UTC)

... Amide#Structure_and_bonding shows its a resonance of more than 2 forms. Could we add "eg. C-N in amides has bond order ~1.20 due to resonance of multiple forms; see Amide#Structure_and_bonding." ? Do we deduce the bond order from the bond energy ? - Rod57 (talk) 13:27, 9 April 2016 (UTC)

It is a nice example that could be added, but skimming through the reference in Amide#Structure_and_bonding, Kemnitz(2007), it seems to suggest the order is more like 1.5, no? Yikkayaya (talk) 13:28, 12 January 2017 (UTC)

Fraction values less stable

Intro says "Those with fractional values exist but are not stable." Is 1.5 considered a fraction value ? Would it be better to say "Those with a bond order less than 1.0 exist but are not stable, eg. ..." ? ?
but later it says "Bond orders of one-half can be stable, as shown by the stability of H⁺
₂ (bond length 106 pm, bond energy 269 kJ/mol) and He⁺
₂ (bond length 108 pm, bond energy 251 kJ/mol)." What bond energy is considered 'stable' ? - Rod57 (talk) 13:08, 9 April 2016 (UTC)

Yeah, contradicting. I removed the "not stable" sentence. - Yikkayaya (talk) 13:30, 12 January 2017 (UTC)

bond order and stability

How can we compare stability between Nitrogen molecule and its ion?Which one is highly stable? Please explain in term of bond order calculation. Alishasapkota (talk) 12:45, 14 June 2016 (UTC)

Briefly: The molecule N₂ has a bond order of 3 and is highly stable against dissociation; it is the major component of the atmosphere. It also has a high ionization energy so is stable against ionization.

The ion N₂⁺ has one less bonding electron so it has a bond order of 2.5; this bond is still quite strong so the ion is stable against dissociation. However the ion tends to react instead by electron capture. The missing electron is easily replaced by one from some other species to form N₂ again. Dirac66 (talk) 14:17, 16 June 2016 (UTC)

Bond order or bond number?

Yesterday the intro was changed to replace the phrase bond order by bond number, apparently based on a (new?) IUPAC definition. The problem with this is that the term bond order is much more commonly used in chemistry, despite IUPAC. Every general chemistry or inorganic chemistry text I checked has bond order in the index and not bond number. I would suggest returning to bond order and adding one sentence to say that IUPAC (and some authors?) prefer the term bond number. If two terms are really used as synonyms, Wikipedia should mention that fact.

Note also that bond number can have other meanings. Some organic chemists will use bond number 3 to describe the (single or double) bond between carbons 3 and 4 in a chain. Also a link to Bond number now redirects to a completely unrelated article on fluid dynamics!

Image

I feel like an image to show molecular orbital theory and how it effects bond order could be added. Osuprunchik (talk) 00:53, 29 January 2020 (UTC)