Optical Properties
Transmission range in µm @10% min. 0.41 - 24.5
Transmission range in µm @50% min. 0.42 - 24.5
Refractive index @ 633nm 2.05678
(1.98 @10µm)
Reflection losses in % at 1 surface 10.82 @ 10µm
Reflection losses in % at 2 surfaces 19.5 @ 10µm
dn/dT in 1/K -61 · 10-6
Physical Properties
Density in g/cm³ 5.589
Melting point in °C 457
Specific heat capacity in J/(kg · K) 355
Thermal Conductivity in W/(m · K) 1.2
Thermal Expansion in 1/K 31 · 10-6
Dielectric constant 12.3
Solubility in water in g/100g 1.9 · 10-4 @ 25°C
Mohs hardness 1.5 - 2
Knoop hardness in kg/mm² 9.5
Material type Single crystal, synthetic
Crystal type cubic
Crystal structure Fm3m
Lattice constant in Å a = 5.547
Elastic coeficients in GPa C11 = 59.6
C12 = 36.1
C44 = 6.22
Young's Modulus (E) in GPa 22.9
Shear Modulus (G) in GPa 7.099
Bulk Modulus (K) in GPa 44.04
Rupture Modulus in MPa 26
Apparent elastic limit in MPa 26.2
Poisson ratio 0.41
Spectral Properties