Chemistry Reference
In-Depth Information
(a)
(b)
i
σ
g
+
σ
u
+
s
1
s
2
i
σ
g
+
σ
u
+
p
z
1
-p
z
2
(c)
π
g
π
u
Figure 7.27
The SALCs for s and p states of a diatomic D
∞h
molecule. (a) The
σ
u
+
combinations of s and of p
z
AOs. (b) The action of the inversion operation for s
1
and p
z
1
.(c)
The
σ
g
+
and
π
g
and
π
u
degenerate pairs formed from p
x
and p
y
orbitals.
Figure 7.28 shows a general MO diagram based on the SALCs we have generated. In
this picture it is assumed that the
-symmetry MOs formed from the s-AOs do not mix
with their counterparts of the same symmetry from p
z
. This will be the case if the energy
σ
σ
u
+
6
π
g
2
p
z
p
x
p
y
p
y
p
x
p
z
2p
2p
π
u
1
σ
g
+
5
σ
u
+
4
2s
2s
σ
g
+
3
Atomic
orbitals
Atomic
orbitals
Figure 7.28
A general MO diagram for diatomic molecules A
2
for second-row elements. This
diagram assumes no hybridization of the
σ
g
+
or
σ
u
+
combinations of s and of p
z
AOs.
