Structural type | A5 |
Common name | beta-tin |
Prototype | β-Sn |
Pearson symbol | tI4 |
Space group | 141 I41/amd D4h19 |
Chemical formula | A |
Bonding | metallic-covalent |
Atomic positions |
A (4a) 0 3/4 1/8 (origin is at the inversion point) |
Coordination | 4+2+4 for c/a>2/sqrt(15) 2+4+4 for c/a<2/sqrt(15) |
PDB files | A5 (ideally packed), 2 unit cells |
Parameters | c/a≥0.52 |
Special cases | best packing for c/a=2/sqrt(15) with δ=8*sqrt(2)/15≈0.75 |
Superstructures | dia for c/a=sqrt(2) |
Substances | high-pressure metallic phase of IV elements |