Optical Properties
Transmission range in µm @10% min. 0.2 - 25
Transmission range in µm @50% min. 0.23 - 25
Refractive index @ 633nm 1.55655
(1.537 @10µm)
Reflection losses in % at 1 surface 4.34 @ 10µm
Reflection losses in % at 2 surfaces 8.3 @ 10.6µm
dn/dT in 1/K -40.83 · 10-6
Physical Properties
Density in g/cm³ 2.7533
Melting point in °C 730
Specific heat capacity in J/(kg · K) 435
Thermal Conductivity in W/(m · K) 4.8
Thermal Expansion in 1/K 43 · 10-6
Dielectric constant 4.9
Solubility in water in g/100g 67.8 @ 25°C
Mohs hardness 1.5
Knoop hardness in kg/mm² 7 (<100>)
Material type Single crystal, synthetic
Crystal type cubic face-centered
Crystal structure Fm3m
Lattice constant in Å a = 6.598
Elastic coeficients in GPa C11 = 34.5
C12 = 5.4
C44 = 5.08
Young's Modulus (E) in GPa 26.8
Shear Modulus (G) in GPa 5.08
Bulk Modulus (K) in GPa 15.03
Rupture Modulus in MPa 3.3
Apparent elastic limit in MPa 3.3
Poisson ratio 0.3
Spectral Properties