Symmetry Lab › D6d › Bis(benzene)chromium, staggered
Cr(C₆H₆)₂ (staggered) Bis(benzene)chromium, staggered
Sandwich, rings staggered by 30° · point group D6d · order 24
- Point group
- D6d — A C6 principal axis, 6 perpendicular C2 axes and 6 dihedral mirror planes that bisect them; the principal axis is also an S12 axis.
- Order
- 24
- Operations
- E, 2S₁₂, 2C₆, 2S₄, 2C₃, 2S₁₂⁵, C₂, 6C₂′, 6σd
- Shape
- Sandwich, rings staggered by 30°
- Atoms
- 25 (Cr, C × 12, H × 12)
Symmetry elements of Cr(C₆H₆)₂ (staggered)
- C₆ — through the metal and both ring centres; also the S₁₂ axis
- C₂′ (1) — perpendicular to the axis, between a carbon above and one below
- C₂′ (2) — perpendicular to the axis, between a carbon above and one below
- C₂′ (3) — perpendicular to the axis, between a carbon above and one below
- C₂′ (4) — perpendicular to the axis, between a carbon above and one below
- C₂′ (5) — perpendicular to the axis, between a carbon above and one below
- C₂′ (6) — perpendicular to the axis, between a carbon above and one below
- S₁₂ — rotate 30°, then reflect: maps one ring onto the other
- S₄ — rotate 90°, then reflect
- σd (1) — contains the axis and one carbon of each ring
- σd (2) — contains the axis and one carbon of each ring
- σd (3) — contains the axis and one carbon of each ring
- σd (4) — contains the axis and one carbon of each ring
- σd (5) — contains the axis and one carbon of each ring
- σd (6) — contains the axis and one carbon of each ring
Structure
- Cr–C 2.15 Å
- Rings staggered by 30°
- The eclipsed form (D6h) is the ground state; the two are only a few kJ/mol apart
