Reynolds
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energy of the molecule is lower than that of the separate atoms because interaction of the
electron within a single atom is much stronger when there is only one nucleus.
Let us now consider the second sigma orbital (2σ), shown in Eq. (1.4) and again in
Figure 1.2. This wavefunction has symmetry identical to that of the 1σ orbital, described
in Eq. (1.3). Schrödinger’s equation calculates that this wavefunction has a higher energy
Figure 1.1. Illustration of localization of electron density in sigma (σ) and pi (π) bonding between
two atoms. The σ bonding between two atoms is shown at the top while π and σ bonding between
two atoms is illustrated underneath.
nodal plane
+
σ
σ *
+
+
-
Figure 1.2. Overlapping molecular orbitals interfering constructively (same signs) and destructively
(different signs). Constructive interference results in a (σ) molecular bonding orbital while destructive interference produces an antibonding sigma (σ*) molecular bonding orbital.
12
energy of the molecule is lower than that of the separate atoms because interaction of the
electron within a single atom is much stronger when there is only one nucleus.
Let us now consider the second sigma orbital (2σ), shown in Eq. (1.4) and again in
Figure 1.2. This wavefunction has symmetry identical to that of the 1σ orbital, described
in Eq. (1.3). Schrödinger’s equation calculates that this wavefunction has a higher energy
Figure 1.1. Illustration of localization of electron density in sigma (σ) and pi (π) bonding between
two atoms. The σ bonding between two atoms is shown at the top while π and σ bonding between
two atoms is illustrated underneath.
nodal plane
+
σ
σ *
+
+
-
Figure 1.2. Overlapping molecular orbitals interfering constructively (same signs) and destructively
(different signs). Constructive interference results in a (σ) molecular bonding orbital while destructive interference produces an antibonding sigma (σ*) molecular bonding orbital.