KPC5

МакроОптика produces mirrors, lenses, windows, prisms, wedges and others optical components according to customers’ specifications and drawings out of crystal Thallium Bromoidide KRS-5

KRS5 deep IR material with a high refractive index.KRs-5 (TlBr-TlI) is a gorgeous red crystal commonly used for attenuated total reflection prisms for IR spectroscopy and in athermalised IR imaging systems. It is also used as an infrared transmission window in gas and liquid sample cells used with FTIR spectrophotometers in place of Potassium Bromide (KBr) or Cesium Iodide (CsI) for analysis of aqueous samples that would attack KBr or CsI optics. It has a wide transmission range and is virtually insoluble in water. It is a useful alternative to AgCl since it is not photo-sensitive and for ATR applications it will transmit well beyond the 18 micron useful range of ZnSe. KRS-5 is considered toxic, but in our opinion it is safe for IR spectroscopic applications when properly handled.

KRS-5 crystalises by the sealed-ampoule Stockbarger technique. Starting materials of the highest purity are selected to ensure that there are no anionic absorption bands between 2μm and 16μm and all crystals are checked for quality by using a pathlength of 120mm.

CAUTION: Thallium salts are considered TOXIC and should be handled with care.

Product Data

Transmission Range 0.6 to 40 μm
Refractive Index 2.371 at 10 μm (1)(3)
Reflection Loss 28.4% at 10 Ојm (2 surfaces)
Absorption Coefficient n/a
Reststrahlen Peak n/a
dn/dT  -235 x 10-6 /В°C
dn/dОј 0: 7 Ојm
Density 7.371 g/cc (3)
Melting Point 414.5 В°C (3)
Thermal Conductivity 0.544 W m-1 K-1 at 293K
Thermal Expansion 58 x 10-6 /В°C (2)
Hardness Knoop 40.2 (2)
Specific Heat Capacity 200 J Kg-1 K-1 at 273K
Dielectric Constant 32.5
Youngs Modulus (E) 15.85 GPa (2)
Shear Modulus (G) 5.79 GPa (2)
Bulk Modulus (K) 19.78 GPa (2)
Elastic Coefficients C11=331; C12=13.2; C44=5.79
Apparent Elastic Limit 26.2 MPa (2)
Poisson Ratio 0.369
Solubility 0.05g/100g water at 293K
Molecular Weight 42 mole% TlBr; 58 mole% TlI
Class/Structure Cubic, CsCl structure, Pm3m, No cleavage (3)

Transmittance

Refractive Index

No = Ordinary Ray

µm No µm No µm No
0.54 2.68059 1.00 2.44620 1.50 2.40774
2.00 2.39498 3.00 2.38574 4.00 2.38204
5.00 2.37979 6.00 2.37797 7.0 2.37627
8.0 2.37452 9.0 2.37267 10.0 2.37069
11.0 2.36854 12.0 2.36622 13.0 2.36371
14.0 2.36101 15.0 2.35812 16.0 2.35502
17.0 2.35173 18.0 2.34822 19.0 2.34451
20.0 2.34058 21.0 2.33643 22.0 2.33206
23.0 2.32746 24.0 2.32264 25.0 2.31758
26.0 2.31229 27.0 2.30676 28.0 2.30098
29.0 2.29495 30.0 2.28867 31.0 2.28212
32.0 2.27531 33.0 2.26823 34.0 2.26087
35.0 2.25322 36.0 2.24528 37.0 2.23705
38.0 2.22850 39.0 2.21965 40.0 2.21047