Symmetry Lab › D3h › Iron pentacarbonyl
Fe(CO)₅ Iron pentacarbonyl
Trigonal bipyramidal · point group D3h · order 12
- Point group
- D3h — A C3 principal axis, 3 perpendicular C2 axes and a horizontal mirror plane; these also give 3 vertical planes.
- Order
- 12
- Operations
- E, 2C₃, 3C₂, σh, 2S₃, 3σᵥ
- Shape
- Trigonal bipyramidal
- Atoms
- 6 (Fe, C × 5)
Symmetry elements of Fe(CO)₅
- C₃ — perpendicular to the plane of three C atoms
- C₂ (1) — along one equatorial Fe–C bond
- C₂ (2) — along one equatorial Fe–C bond
- C₂ (3) — along one equatorial Fe–C bond
- σh — the plane of the three equatorial C atoms
- σᵥ (1) — contains the C₃ axis and one equatorial bond
- σᵥ (2) — contains the C₃ axis and one equatorial bond
- σᵥ (3) — contains the C₃ axis and one equatorial bond
- S₃ — rotate 120°, then reflect in σh
Structure
- Fe–C ≈ 1.80 Å (carbons shown; each carries a C≡O)
- Trigonal bipyramid at Fe
- 18-electron complex
