GERMANIUM by Generic IR

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Refractive Index vs Wavelength
Refractive Index Calculator
Valid range: 2.0–15.0 µm
dn/dλ vs Wavelength
dn/dλ Calculator
Valid range: 2.0–15.0 µm
Abbe Number Calculator
Transmission vs Wavelength
Transmission Calculator
Valid wavelength range: 1.653–15.000 µm
Optical Properties
Refractive Index (nd)
Abbe Number (Vd)
Dispersion Formula Sellmeier 4
Wavelength Range 2.0 — 15.0 µm
$$n(\lambda) = \sqrt{9.28065 + \frac{6.73019\,\lambda^2}{\lambda^2 - 0.441837} + \frac{0.213137\,\lambda^2}{\lambda^2 - 3870.35}}$$
Thermal Properties
TCE -30/70°C (10-6/K) 5.7
TCE 100/300°C (10-6/K)
Thermal Conductivity (W/mK)
Heat Capacity (J/gK)
$$\frac{dn}{dT} = \frac{n_0^2 - 1}{2\,n_0}\left[0.00022 + 2(0)\,\Delta T + 3(0)\,\Delta T^2 + \frac{0 + 2(0)\,\Delta T}{\lambda - 0}\right] \Delta T = T - T_0, \quad T_0 = 20.15\,°\text{C}$$
Physical Properties
Density (g/cm³) 5.327
Relative Cost
Mechanical Properties
Young's Modulus (GPa)
Poisson's Ratio
Knoop Hardness (kgf/mm²)
Chemical Resistance
Climatic Resistance
Stain Resistance
Acid Resistance
Alkali Resistance
Phosphate Resistance
Notes

source: Handbook of Optical Constants of Solids

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