Introduction - This script shows some properties of the α-helix.
Scroll down until the text corresponding to the view is visible.
In this "peptide" the phi and psi angles have been set to those
corresponding to the alpha helix.
Here is an alpha helix. Note the pattern of hydrogen bonding
(GREEN) - the hydrogen
bonds are intrachain and form between elements of the peptide bond
that separated by four residues in the primary sequence.