Standard Origins and Orientations

3DEM Image Conventions

Dihedral Symmetry



Standard orientation:  principal symmetry axis is aligned with the z-axis, 2-fold axis aligned with x-axis

Standard origin:  intersection of symmetry axis



 Standard  Orientation (standard display orientation) Standard Orientation (view down x-axis, 2-fold axis) Standard Orientation (arbitrary display orientation)
Odd-numbered Principal Axis (D5),
Example 1		 Example 1, D5 symmetry, standard orientation, standard display orientation
 Example 1, D5 symmetry, standard orientation, view down x-axis (2-fold axis) Example 1, D5 symmetry, standard orientation, arbitrary display orientation
Odd-numbered Principal Axis (D5),
Example 2
 Example 2, D5 symmetry, standard orientation, standard display orientation Example 2, D5 symmetry, standard orientation, view down x-axis (2-fold axis) Example 2, D5 symmetry, standard orientation, arbitrary display orientation
Even-numbered Principal Axis (D6)
Example 1		 Example 1, D6 symmetry, standard orientation, standard display orientation Example 1, D6 symmetry, standard orientation, view down x-axis (2-fold axis) Example 1, D6 symmetry, standard orientation, arbitrary display orientation
Even-numbered Principal Axis (D6)
Example 2		 Example 2, D6 symmetry, standard orientation, standard display orientation Example 2, D6 symmetry, standard orientation, view down x-axis (2-fold axis) Example 2, D6 symmetry, standard orientation, arbitrary display orientation



Back to standard origins/orientations table
11 Feb 2006