A dihedral group is the group of all symmetries (reflections & rotations) of a regular polygon. Dihedral groups are among the simplest examples of finite groups which play an important role in group theory, geometry, and chemistry. 🦋 | 𝑶𝒑𝒆𝒏𝑴𝒂𝒕𝒉𝑪𝒊𝒓𝒄𝒍𝒆

Group Therapy | Definition, Types & Examples

SOLVED:(a) Identify the symmetry elements in ethene and in allene, and assign each molecule to a point group. (b) Consider the biphenyl molecule, Ph-Ph, in which different conformations are possible according to the value of the dihedral angle between the planes of the two benzene rings: if this angle is 0^∘ the molecule is planar, if it is 90^∘, the two rings are perpendicular to one another. For each of the following dihedral angles, identify the symmetry elements (i) 0^∘ (iii) 45^∘ present an