Rotation around the C-C bond in ethane

The simplest n-alkane is ethane, C₂H₆. The bond between the two carbon atoms is a single ('sigma') bond, that is rotation symmetric with respect to the C-C axis, so it allows rotation around this axis. When rotating around this carbon-carbon bond, the energy of ethane varies because of the presence of the C-H bonds.
Have a look at the energy as a function of the rotation around the carbon-carbon bond in ethane. Such a plot you will also find in your textbook.

Use these animation control buttons, or click on a point in the graph.

Energies are from AM1 calculations and are for qualitative discussion only. Better calculations would give different quantitative results. This page was adapted by Bob Hanson for Internet Explorer 4 and Netscape 7 from the original, written by Hens Borkent