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Symmetry Lab › D3h › Boron tribromide

BBr₃ Boron tribromide

Trigonal planar · point group D3h · order 12

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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 planar
Atoms
4 (B, Br × 3)

Symmetry elements of BBr₃

  • C₃ — perpendicular to the plane of three Br atoms
  • C₂ (1) — along one B–Br bond
  • C₂ (2) — along one B–Br bond
  • C₂ (3) — along one B–Br bond
  • σh — the plane of the three Br atoms
  • σᵥ (1) — contains the C₃ axis and one bond
  • σᵥ (2) — contains the C₃ axis and one bond
  • σᵥ (3) — contains the C₃ axis and one bond
  • S₃ — rotate 120°, then reflect in σh

Structure

  • B–Br 1.89 Å
  • Br–B–Br 120°
  • No lone pair on B
Boron tribromide (BBr3) — D3h symmetry elements
Boron tribromide: symmetry elements of the D3h point group

Other D3h molecules

Open in the 3D lab →  ·  All D3h molecules  ·  All point groups