Use molecular orbital theory to explain why the Be2 molecule does not exist.

The electronic configuration of Beryllium is.

The molecular orbital electronic configuration for Be2 molecule can be written as:


Hence, the bond order for Be2 is


Where,


Nb = Number of electrons in bonding orbitals


Na = Number of electrons in anti-bonding orbitals


Bond order of Be2 = 0


A negative or zero bond order means that the molecule is unstable. Hence, Be2molecule does not exist.


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