Newman+Projections

A Newman projection is one way of showing the bond angles and atomic arrangements about a carbon-carbon bond. It focuses on two carbons.

For the molecule ethane (CH3CH3), the Newman projection looks like this:



Note that you are actually looking straight down the C-C bond, which puts the hydrogens out at 120 degrees from each other.

Here is a visualization for propane (C3H8):

Note that the Newman projection changes depending on how you look down the C-C bond.

It will also change as the C-C bond rotates.

When the atoms are adjacent from one another, as shown in the above projections, they are in a //staggered// conformation. If they line up (one in front of the other) they are in an //eclipsed// conformation.

Here are the Newman projections for butane (C4H10):

When atoms or branches are adjacent one another they are considered //gauche//. When they are 180 degrees apart, they are called //anti.//

Examine the Newman projection for isoleucine: