Molecules 271
Figure 8.5 (a)–(d) The combination of two hydrogen-atom 1swave functions to form the symmetric
H 2 wave function S. The result is a stable H 2 molecular ion because the electron has a greater
probability of being between the protons than outside them. (e) If the protons could join together,
the resulting wave function would be the same as the 1swave function of a Heion.
a 0
(a)
(b)
(c)
(d)
(e)
r
a
a
Contours of
electron probability
+
r
b
b
+
r
a
R
S
b
+ +
r
a
R
S
b
+ +
r
R = 0
He+(1s)
2+
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