I am trying to find the symmetry operations of the rhombohedron (Trigonal prism, Trigonal trapezohedral). I've already found this has 12 symmetry operations and 1 is identity and 4 is for rotational symmetry (one 3-fold symmetry and three 2-fold symmetry).
I'm trying to identify other symmetry operations such as plane of symmetry and center of symmetry. My calculations suggest that there is 7 plane of symmetries. (Which I'm unsure of) Can someone help me and point me in the right direction lease?