It is clearly seen that in the region between the nuclei the value of is greater than the sum of and . This feature is the central theme of chemical bonding, ie, the charge density between the nuclei is different (generally larger) than the sum of the individual charge densities of the respective atomic orbitals. We will elaborate the meaning of 2 a little latter in this lecture.
In fig 7.5, the plot of the MO 1 as a function of the x and y coordinates of the plane is shown. The highest value of the function is 1.83 -3/2 at two points near each of the two nuclei. Can you rationalize why the maximum value occurs at two places?
Fig 7.5 A 3 -dimensional plot of the MO. The value of 1at the peaks is 1.83 -3/2
If we view the molecule along the internuclear axis (and not perpendicular the internuclear axis that we have been doing so far), then the contours are all circular. The MO is often shown as a perspective plot (fig 7.6 (a)) or as an overlap diagram (fig 7.6 (b)) as shown below.
(7.6a) (7.6b)
Figure 7.6 (a) Perspective plot of the MO1. Fig 7.6 (b) The MO - overlap diagram of 1
is greater than the sum of 
and 
. This feature is the central theme of chemical bonding, ie, the charge density between the nuclei is different (generally larger) than the sum of the individual charge densities of the respective atomic orbitals. We will elaborate the meaning of 
2 a little latter in this lecture. 
1 as a function of the x and y coordinates of the plane is shown. The highest value of the function is 1.83 
-3/2 at two points near each of the two nuclei. Can you rationalize why the maximum value occurs at two places? 
