Molecules may have many rotation axes. But the axis with the highest n is designated as the principal axis C? . The operation Cl is merely E 20218/21 Chemistry Departme nt of Fudan University 11
Physical ChemistryI Chemistry Department of Fudan University Chapter IV Molecular Symmetry and Point Group 2021/8/21 11 Molecules may have many rotation axes. But the axis with the highest n is designated as the principal axis •The operation C1 is merely E
3. Symmetry Planes and Reflections There are 3 types of planes Vertical, horizontal and dihedral 20218/21 Chemistry Departme nt of Fudan University
Physical ChemistryI Chemistry Department of Fudan University Chapter IV Molecular Symmetry and Point Group 2021/8/21 12 3. Symmetry Planes and Reflections There are 3 types of planes: Vertical, horizontal and dihedral
Vertical Oy If the reflection plane contains the Principle axis. it is called a vertical plane” 20218/21 Chemistry Departme nt of Fudan University
Physical ChemistryI Chemistry Department of Fudan University Chapter IV Molecular Symmetry and Point Group 2021/8/21 13 Vertical v If the reflection plane contains the Principle Axis, it is called a “vertical plane
Horizontal planeσh If the reflection plane is perpendicular to the principle axis, it is called a “ horizontal plane” A molecule can have only one Oh 20218/21 Chemistry Departme nt of Fudan University 14
Physical ChemistryI Chemistry Department of Fudan University Chapter IV Molecular Symmetry and Point Group 2021/8/21 14 If the reflection plane is perpendicular to the Principle Axis, it is called a “horizontal plane.” Horizontal plane h N N h C A molecule can have only one h
Dihedral od Vertical planes which bisect the angles between adjacent pairs of C2 axes perpendicular to the principle axis eneE 20218/21 Chemistry Departme nt of Fudan University
Physical ChemistryI Chemistry Department of Fudan University Chapter IV Molecular Symmetry and Point Group 2021/8/21 15 C C C H H H H C2 ' C2 ' C2 , S4 Dihedral d Vertical planes which bisect the angles between adjacent pairs of C2 axes perpendicular to the principle axis