Symmetry Lab › D2d › Tetrasulfur tetranitride
S₄N₄ Tetrasulfur tetranitride
Cradle: S₄ tetrahedron threaded through an N₄ square · point group D2d · order 8
- Point group
- D2d — A C2 principal axis, 2 perpendicular C2 axes and 2 dihedral mirror planes that bisect them; the principal axis is also an S4 axis.
- Order
- 8
- Operations
- E, 2S₄, C₂, 2C₂′, 2σd
- Shape
- Cradle: S₄ tetrahedron threaded through an N₄ square
- Atoms
- 8 (S × 4, N × 4)
Symmetry elements of S₄N₄
- C₂ — through the cage centre
- S₄ — rotate 90° then reflect: swaps the upper and lower S pair
- C₂′ (1) — through two opposite N atoms
- C₂′ (2) — through the other two N
- σd (1) — contains the lower S pair, bisects the upper
- σd (2) — contains the upper S pair, bisects the lower
Structure
- S–N 1.62 Å
- S···S 2.58 Å across the cage (a weak bond)
- The four N lie in one plane; the S atoms sit above and below
