Bismuth
post-transition metal · period 6 · group 15 (pnictogens) · p-block
Bismuth is a chemical element with the symbol Bi and atomic number 83. It is a pentavalent post-transition metal and one of the pnictogens with chemical properties resembling its lighter group 15 siblings arsenic and antimony.
What the numbers say
At standard temperature and pressure Bismuth is a solid, sitting in period 6, group 15 of the p-block.
Its melting point of 545 K (272 °C) is the 81st highest of the 110 elements with a measured value — mid-range among the elements.
At 9.78 g/cm³ it is the 29th densest of 96 elements with a quoted density.
Pauling electronegativity is 2.02. Paired with oxygen (3.44) that is a difference of 1.42, which puts the bond polar covalent — oxides here tend to be semiconducting or refractory rather than salt-like.
In the solid state it takes a base-centered monoclinic structure.
It is reported in 3 oxidation states (-3, 3, 5), which sets how many distinct compounds and phases it can form.
First identified in 1400.
Crystal structure
Solid Bismuth adopts a Base-centered Monoclinic arrangement, in the Monoclinic system — axes a ≠ b ≠ c, angles α = γ = 90°, β ≠ 90°. Symmetry controls the anisotropy of stiffness and thermal expansion, and the available slip systems set how far the metal deforms before it fractures.
Crystallographic examples
Bismuth or one of its compounds is a textbook example for this crystal system:
- Trigonal (rhombohedral) — α-quartz, calcite CaCO₃, Bi, corundum Al₂O₃
Check it against computed structures
The structure search queries the Materials Project, OQMD and the Open Materials Database for computed crystal structures containing Bi — with DFT formation energy, hull stability and band gap where the provider publishes them.
K 2 · L 8 · M 18 · N 32 · O 18 · P 5
Properties
| Atomic number | 83 |
|---|---|
| Atomic mass | 208.980401 u |
| Series | post-transition metal |
| Group | 15 |
| Period | 6 |
| Block | p-block |
| Phase at STP | Solid |
| Density | 9.78 g/cm³ |
| Melting point | 544.7 K (272 °C) |
| Boiling point | 1837 K (1564 °C) |
| Electronegativity (Pauling) | 2.02 |
| Electron configuration | [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p³ |
| Crystal structure | Base-centered Monoclinic |
| Oxidation states | -3,3,5 |
| Discovered | 1400 |
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See Bi in context with all 118 elements.
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