• Mendelstraße 11,
    D-48149 Münster

Thalliumbromidiodid (KRS-5)

Material
KRS-5

 

Thalliumbromidiodid (KRS-5) is a material for use in the far-infrared range. It has a wide transparency spectrum from 0.6-40 µm. KRS-5 is used for the manufacture of ATR (attenuated total reflection) prisms, windows and lenses for spectroscopy and astronomical telescopes. In combination with germanium, KRS-5 is also used for athermal IR imaging.

Tallium bromodioxide is prone to cold deformation, which can change its shape over time. In addition, KRS-5 is toxic as a thallium solid solution, so the material must be handled with care.

Properties
Optical and spectral properties
Transmission range in µm (minimum 10%)
0,57‐40
Transmission range in µm (minimum 50%)
0,56‐40
Refractive index @633nm
2,573

(2,371 @10,6µm)

Reflection losses in % at 1 surface
16,53 @10µm
Reflection losses, % for two surfaces
28,4 @10µm
dN/dT in 1/K
-235 · 10-6
Physical properties
Density in g/cm3
7,365
Melting point in °C
414,5
Specific heat capacity in J/(kg · K)
160
Thermal conductivity in W/(m · K)
0,544 @293K
Thermal expansion in 1/K
58 · 10-6 @293‐373
Dielectric constant
32,5
Solubility in water in g/100g
0,05
Mohs hardness
–
Knoop hardness in kg/mm²
40,2 <100>
Material type
single crystalline, synthetic
Crystal type
cubic, CsCl structure
Crystal structure
F43m
Lattice constant in Å
a = 4,11
Elastic coefficient in GPa
C11 = 34,1

C12 = 13,6

C44 = 5,79

Young's Modulus (E) in Gpa
15,85
Shear Modulus (G) in GPa
5,79
Bulk Modulus (K) in GPa
19,78
Rupture Modulus in MPa
26,2
Apparent elastic limit in MPa
26,2
Poisson's ratio
0,34
Spectral properties
sample thickness: 2 mm
Optical Properties
Transmission range in µm @10% min. 0.56 - 40
Transmission range in µm @50% min. 0.57 - 40
Refractive index @633nm 2.57288
(2.371 @10.6µm)
Reflection losses in % at 1 surface 16.53 @10µm
Reflection losses in % at 2 surfaces 28.4 @10µm
dn/dT in 1/K -235· 10-6
Physical Properties
Density in g/cm³ 7.365
Melting point in °C 414.5
Specific heat capacity in J/(kg · K) 160
Thermal Conductivity in W/(m · K) 0.544 @293K
Thermal Expansion in 1/K 58 · 10-6 @293-373K
Dielectric constant 32.5
Solubility in water in g/100g 0.05
Mohs hardness
Knoop hardness in kg/mm² 40.2 <100>
Material type Single crystal, synthetic
Crystal type cubic, CsCl structure
Crystal structure Pm3m
Lattice constant in Å a = 4.11
Elastic coeficients in GPa C11 = 34.1
C12 = 13.6
C44 = 5.79
Young's Modulus (E) in GPa 15.85
Shear Modulus (G) in GPa 5.79
Bulk Modulus (K) in GPa 19.78
Rupture Modulus in MPa 26.2
Apparent elastic limit in MPa 26.2
Poisson ratio 0.34
Spectral Properties
Back to materials
Back to materials
To stock
To stock
To contact
To contact