bei48482_FM

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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