Thallium (Tl) is a soft, dense post-transition metal with low melting point and high toxicity, belonging to Group 13 of the periodic table. Historically used in specialized optical applications (infrared lenses, scintillation detectors) and legacy electronics, thallium has largely been phased out of most industrial applications due to severe health and environmental hazards; modern engineering selection favors safer alternatives. When encountered in active use, it typically appears in niche scientific instrumentation, certain photomultiplier tubes, or specialized research contexts where its unique optical and radiation properties justify the toxicity risks and regulatory constraints.
Compliance & Regulations
| Property | Value | Unit | Conditions | Source | |
|---|---|---|---|---|---|
Bulk Modulus(K)2 entries | 26.38 | GPa | — | ||
| ↳ | 30.66 | GPa | — | ||
Elastic Compliance Tensor(Sij) | Matrix (redacted) | 1/GPa | — | ||
Elastic Anisotropy(AU) | 0.5403 | - | — | ||
Elastic Stiffness Tensor(Cij) | Matrix (redacted) | Pa | — | ||
Poisson's Ratio(ν)2 entries | 0.3809 | - | — | ||
| ↳ | 0.4100 | - | — | ||
Shear Modulus(G)2 entries | 6.823 | GPa | — | ||
| ↳ | 6.450 | GPa | — |
| Property | Value | Unit | Conditions | Source | |
|---|---|---|---|---|---|
Density(ρ) | 11.10 | kg/m³ | — |
| Property | Value | Unit | Conditions | Source | |
|---|---|---|---|---|---|
Band Gap(Eg) | 0.000 | eV | — | ||
Magnetic Moment(μB) | 0.000 | µB | — | ||
Seebeck Coefficient(S) | -3.820 | µV/K | — |
| Property | Value | Unit | Conditions | Source | |
|---|---|---|---|---|---|
Energy Above Hull(ΔEhull) | 0.000 | eV/atom | — | ||
Formation Energy(ΔHf) | 0.000 | eV/atom | — |