Page 76 - Science at the nanoscale

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RPS: PSP0007 - Science-at-Nanoscale
June 12, 2009
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From Atoms and Molecules to Nanoscale Materials
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Figure 4.3.
Wave function plots for the interacting orbitals of H A and
H B .
< (ı *)
ȥ (1s)
H atom
H atom
Ȍ (ı )
H 2 ȥ (1s) ch04
Figure 4.4. Schematic MO energy level diagram for H 2 molecule, with
2 electrons of opposite spins occupying the bonding orbital.
the two H atoms (Fig. 4.4). In the case of He, we know that the
He 2 molecule is not stable since the occupancy of σ and σ MOs
∗
by four electrons cancel out the bonding interaction.
For N 2 molecules, the MO picture must be extended to include
2s and 2p AOs. The schematic MO energy level diagram is given
in Fig. 4.5, with the wavefunction notation removed for simplicity.