KRS-5 (Thallium Bromide Iodide)

lenses, windows, mirrors, filters and prisms



KRS-5 (Thallium Bromide Iodide) is used for ATR (attenuated total reflection) prisms, infrared windows and lenses from 0.6-40 microns. KRS-5 is only slightly soluble in water but can be attacked by some solvents and acids. This material is relatively soft and care should be taken during handling and processing.

Caution: Thallium compounds are classified as toxic and must be handled with care.


Transmission Range 0.6 – 40.0 µ
Crystal Structure Caesium chloride
Cleavage Plane None
Colour Deep Red
Density 7.371 (16°)
Melting Point (°) 414.5
Reflection Loss 28.4% (10µ) for 2 surfaces
Solubility index 0.02gm/100gm water / 10°C
Hardness (Knoop) 40.2
Thermal Conductivity (cal/cm sec°C) 1.3×10-3 (20°C)
Thermal Expansion coefficient (/°C) 58×10-6 (20-100°C)
KRS-5 (Thallium Bromide Iodide) windows and KRS-5 (Thallium Bromide Iodide) lenses

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