Crystal Type

cubic, NaCl type structure

Transmission Range

0.21 ... 30 µm

Refractive Index

1.488 @ 0.6 µm
1.454 @ 10.6 µm

Reflective Loss

6.8 % @ 10.0 µm

Reststrahlen

63.1 µm

Density^.

1.989 g/cm³

Melting Point

776 °C

Molecular Weight

74.551

Thermal Conductivity

6.53 W/(m K)

Specific Heat

690 J/(kg K)

Thermal Expansion

36 × 10^–6 / K

Hardness (Knoop)

7.2 <110>
9.3 <100>

Young’s Modulus

29.6 / 38.1 GPa

Shear Modulus

6.24 GPa

Bulk Modulus

17.36 GPa

Rupture Modulus

4.41 × 10^–3 MPa

Elastic Coefficient

C¹¹ = 40.2 
C¹² = 6.7 
C⁴⁴ = 6.29 GPa

Dielectric Constant

4.64 @ 25 °C, f = 1 MHz

Solubility in Water

34.7 g / 100 g @ 20 °C

Crystal Structure

Single crystal, synthetic

Cleavage Planes

(100)

Standard Diameter

180 mm
bigger diameter on request

Application

IR spectroscopy
windows for CO² lasers
protection windows for cutting lenses

Remarks

coating available
high laser radiation resistance