Models of hexahelicene enantiomers are shown below. The configuration is determined by the turn made by the carbon atoms in space when viewed along the axis of the helix. A clockwise turn that moves atoms from near to far (darkred to orange) is P (positive) and may also be termed Ra. Likewise, a counterclockwise turn that moves atoms away from the viewer is designated M (minus) or Sa. The buttons beneath each model change the display as indicated. In the axes display, the structure may be rotated about an axis by clicking on the end.