Barium fluoride

Barium fluoride (BaF₂) is a valuable optical material widely employed as an optical window owing to its exceptional properties. With excellent transparency spanning a broad spectral range, particularly in the ultraviolet (UV) and infrared (IR) regions, BaF₂ serves as an ideal choice for optical systems enabling efficient light collection. 

BaF₂'s transmission in the UV spectrum is particularly notable, rendering it suitable for employment in UV optical systems. Consequently, BaF₂ windows find common usage in spectroscopic instruments, facilitating sample analysis across UV, visible, and IR wavelengths.

However, it's important to note that BaF₂ is sensitive to thermal and mechanical shock and is comparatively less resistant to water damage than some other optical materials.

In summary, Barium fluoride emerges as an important optical material for applications demanding high transmission, low absorption, and UV-IR transparency. Its unique attributes make it suitable for a range of scientific, industrial, and imaging systems.

Barium Fluoride (BaF2) is an optical material with the following technical properties:

Transmission Range: 0.15 to 12 μm

Refractive Index: 1.45 at 5 μm

Reflection Loss: 6.5% at 5 μm (2 surfaces)

Absorption Coefficient: 3.2 x 10 -4 cm -1 @ 6 μm

Density: 4.89 g/cc

Melting Point: 1386°C

Thermal Conductivity: 11.72 W m -1 K -1 @ 286 K

Thermal Expansion: 18.1 x 10 -6 K -1 @ 273 K

Hardness Knoop: 82 with 500g indenter

Specific Heat Capacity: 410 J Kg -1 K -1

Dielectric Constant: 7.33 at 1 MHz

Young’s Modulus (E): 53.07 GPa

Shear Modulus (G): 25.4 GPa

Bulk Modulus (K): 56.4 GPa

Apparent Elastic Limit: 26.9 MPa

Poisson Ratio: 0.343

Solubility: 0.17g/100g water at 23°C

Molecular Weight: 175.36

Class/Structure: Cubic Fm3m (#225), Fluorite structure

Please note that these values are typical and may vary based on the grade and manufacturing process of the material