p2
Two-fold rotations only. Centers in four different locations.
From Kathy Paur:
From Simon Gregg:
p2mm
Perpendicular mirrors.
Two-fold rotations with centers in four different locations.
From Kathy Paur:
p2mg
Mirrors perpendicular to glide reflections.
Two-fold rotations with centers in two different locations.
p2gg
Perpendicular glide reflections.
Two-fold rotations with centers in three different locations.
c2mm
Perpendicular mirrors.
Perpendicular glide reflections.
Two-fold rotations with centers in three different locations.
From Kathy Paur:
