Crystal properties
Crystal Type	cubic, NaCl  type structure
Transmission Range	0.23 ... 25 µm
Refractive Index	1.52695 @ 9.724 µm
Reflective Loss	8.4 % @ 10.0 µm
Reststrahlen	77.6 µm
Density	2.7533 g/cm3
Melting Point	730 °C
Molecular Weight	119.002
Thermal Conductivity	4.816 W/(m K) @ 46 °C
Specific Heat	435 J/(kg K) @ 0 °C
Thermal Expansion	43 × 10–6 / K
Hardness (Knoop)	5.9 <110> 7.0 <100> Indenter load 200 g
Young’s Modulus	26.8 GPa
Shear Modulus	5.08 GPa
Bulk Modulus	15.03 GPa
Rupture Modulus	0.33 MPa
Elastic Coefficient	C11 = 34.5 C12 = 5.4 C44 = 5.08 GPa
Dielectric Constant	5.65 @ 25 °C, f = 100 Hz ... 10 GHz
Solubility in Water	53.4 g / 100 g @ 0 °C
Crystal Structure	Single crystal,  synthetic
Cleavage Planes	(100)
Standard Diameter	180 mm
Application	IR spectroscopy FTIR beamsplitters CO2 laser optics protective windows
Remarks	coatings available
List of optical crystals