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1. Plane

   Linked via "Platonic solids"

   The concept of reflectional symmetry is intrinsically linked to the plane. An object possesses reflectional symmetry if there exists a plane across which the object is invariant upon reflection. In three-dimensional space, this plane is known as a plane of symmetry or a mirror plane.
   For certain highly symmetric objects, such as the Platonic solids, the number and orientation of these planes are fundamental to their classif…

2. Point Group

   Linked via "Platonic solids"

   High Symmetry Groups
   Groups with many symmetry elements are often classified as high symmetry or Platonic groups, corresponding to the symmetry of the Platonic solids:
   Tetrahedral Group ($Td$): Possesses the symmetry of a tetrahedron, including $4C3$ axes, $3C2$ axes, and $6\sigmad$ (dihedral mirror planes). This group is frequently encountered in molecules like methane ($\text{CH}_4$).