Symmetry Lab › D3h › Tricyanomethanide ion
C(CN)₃⁻ Tricyanomethanide ion
Planar, three arms · 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
- Planar, three arms
- Atoms
- 7 (C × 4, N × 3)
Symmetry elements of C(CN)₃⁻
- C₃ — perpendicular to the plane
- C₂ (1) — in the plane, along one C–C≡N arm
- C₂ (2) — in the plane, along one C–C≡N arm
- C₂ (3) — in the plane, along one C–C≡N arm
- σh — the plane of the molecule
- σᵥ (1) — perpendicular to the plane; in the plane, along one C–C≡N arm
- σᵥ (2) — perpendicular to the plane; in the plane, along one C–C≡N arm
- σᵥ (3) — perpendicular to the plane; in the plane, along one C–C≡N arm
- S₃ — rotate 120°, then reflect in σh
Structure
- C–C 1.41 Å, C≡N 1.15 Å
- All arms linear, 120° apart
- A planar, delocalised anion
