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Urgent help in molecular orbital diagram

If we were to construct the molecular orbital diagram for CN- the order of filling will be :

σ1s , σ*1s , σ2s , σ*2s , π2p π2p , σ 2p , π*2p π*2p , σ*2p

Am I right?
Thanks a lot
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Original post by >>MMM<<
If we were to construct the molecular orbital diagram for CN- the order of filling will be :

σ1s , σ*1s , σ2s , σ*2s , π2p π2p , σ 2p , π*2p π*2p , σ*2p

Am I right?
Thanks a lot


Why π2p before σ 2p?

Direct orbital overlap is always lower in energy than lateral ..
I believe mixing occurs between the orbitals, which causes the σ 2p orbital to be pushed higher in energy above the π2p.
This can be explained because the elements are both early in the series and therefore the effective nuclear charge is not strong enough to significantly lower the energy of the orbitals to prevent their interaction. Therefore, their energies are similar causing overlap and mixing.

So yes, I would agree with the order you have used above. Best of luck!
Original post by charco
Why π2p before σ 2p?

Direct orbital overlap is always lower in energy than lateral ..



I believe mixing occurs between the orbitals, which causes the σ 2p orbital to be pushed higher in energy above the π2p.
This can be explained because the elements are both early in the series and therefore the effective nuclear charge is not strong enough to significantly lower the energy of the orbitals to prevent their interaction. Therefore, their energies are similar causing overlap and mixing.

So yes, I would agree with the order you have used above. Best of luck!

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