What is bond order? How we can determine it? Please basics. Thank you so much.
A conceptual approach is to simply count electrons in a bond and treat each bonding valence electron as half a bond order.
This works for many cases, except for when the highest-energy electron is in an antibonding molecular orbital.
For example, the bond order of
#"BO"_"triple" = "BO"_sigma + 2"BO"_pi = 1/2 xx ("2 electrons") + 2(1/2 xx ("2 electrons")) = 3#for the bond order, as we should expect, since bond order tells you the "degree" of bonding.
Or, in a more complicated example, like
That means its
#"BO" = "BO"_sigma + "BO"_pi = 1 + 0.333 = 1.333#.
EXCEPTION EXAMPLE: O2
If we were to calculate its bond order, we would get
But what if we wanted the bond order for
You may realize that we would have removed one electron from an
So, by removing an antibonding electron, we've done the equivalent of adding a bonding electron.
In other words, we've decreased a bond-weakening factor, thereby increasing the bonding ability of the molecule.
Therefore, the actual bond order of
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