Potassium chloride
KCl

Chart 1

Chart 2

Crystal properties

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