Essentials of molecular orbital theory

Molecule Configuration Bond energy Bond length Remark 

He+ 251 108 This bond is slightly weaker than that in 

To conclude this section, we apply the energy level diagram in Fig. 3.1.4 to four simple molecules having one to four electrons. The results are summarized in Table 3.1.1. 

Examining Table 3.1.1, we see that our simple treatment is able to rationalize, at least semi-quantitatively, the formation of H2 and the non-existence of He2. 

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