(click
here for enlarged image)We can add significantly to the toplogy of our contours by turning them into mesh plots. A mesh plot elevates the contours by their order of magnitude perpendicular to the plane of the contours. Much like looking at a contour map of mountain, then actually looking at the mountain.
In the images that follow, green represents a value of zero. The colors shift from yellow to red as the elevation (electron density) increases; light blue to dark blue as the elevation decreases.
First lets look directly into the plane of the electron density of two non-interacting hydrogen atoms.
(click
here for enlarged image)
This is simply a plot of the electron density along the nuclear axis. Now lets tilt the plane a little.
(click
here for enlarged image)
Finally looking down on the plane, we see a colorized version of our first 2-dimensional contour map.
(click
here for enlarged image)
The same three views follow for molecular hydrogen. Looking directly into the plane of the electron density.
(click
here for enlarged image)
Again, we can compare this image with the plot of the electron density along the nuclear axis. Tilting the plane a little.
(click
here for enlarged image)
And, looking down on the plane.
(click
here for enlarged image)
Now for the density difference plots.
(click
here for enlarged image)
We see a large lump between the nuclei. This lump is a the difference in electron density between molecular hydrogen and two seperate hydrogen atoms. It is effectively the bonding electron density. Tilting the plane a little reveals the blue regions of negative electron distribution. When the hydrogen atoms form a bond, electron density is pulled away from the outer regions and pulled into the bonding region.
(click
here for enlarged image)
And, looking down on the plane.
(click
here for enlarged image)
In the near future, I plan on expanding what I have into a large summary covering the diatomics from hydrogen through chlorine. To go back click here .
