Thallium - 81Tl: physical properties
Density properties
Density of solid: 11850 kg m‑3
Molar volume: 17.22 cm3
Elastic properties
Young's modulus: 8 GPa
Rigidity modulus: 2.8 GPa
Bulk modulus: 43 GPa
Poisson's ratio: 0.45 (no units)
Hardnesses
Mineral hardness: 1.2 (no units)
Brinell hardness: 26.4 MN m-2
Vickers hardness: (no data) MN m-2
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Electrical properties
Electrical resistivity: 15 × 10‑8 Ω m; or mΩ cm
Heat and conduction
Thermal conductivity: 46 W m‑1 K‑1
Coefficient of linear thermal expansion: 29.9 × 10‑6 K‑1
Optical properties
Reflectivity: (no data) %
Refractive index: (no data) (no units)
Acoustic properties
Velocity of sound: 818 m s‑1