Barium fluoride, BaF2, crystal has good transmittance over a wide spectrum range, from 150 nm to 12.5 um. It has been widely used as windows, lenses, and prisms, particularly for ultaviolet transmittance. The highest quality BaF2 has been used for scintillation crystals. BaF2 can also be used a crystal substrates for the epitaxial growth of thin films.

MSE Supplies offers the following choices:

Customized crystal growth and machining
High quality blank BaF2 crystal materials in discs, plates, rods, customized for customers
Crystal orientations: (100), (111) or other custom-made orientations
Standard BaF2 substrate sizes: 10 mm x 10 mm x 1.0 mm, 1 inch diameter x 1.0 mm
Surface polishing: Single Side Polished (SSP) or Double Side Polished (DSP)
High quality BaF2 scintillation crystal
Customized BaF2 optics for IR and VUV applications
BaF2 viewport windows for Infrared thermography from 8 um to 14 um.

Capability:

Maximum diameter: 7 inches (180 mm)
Surface quality: S/D 20/10 for optical windows or other optical components, Ra < 20 A for epi-ready crystal substrates

Optical Properties
Transmission Range	150 nm to 14 um
Transmittance	>94% at 350 nm to 10.8 um
Refractive Index	1.4624 at 2.58 um 1.3936 at 10.35 um
Reflection Loss	6.8% at 2.58 um (both surfaces) 5.3% at 10.35 um (both surfaces)
Radiation Length	20.6 mm
Residual Radiation Peak	47 nm
Emission Peak	310 nm slow; 220 nm fast
Decay Constant	620 ns slow; 0.6 ns fast
Light Output	20% slow; 4% fast
Absorption Coefficient	3.2 x 10^-4 cm-1 at 6 um
Physical Properties
Density	4.89 g/cm3
Melting Point	1280 °C
Thermal Conductivity	11.72 W.m-1K-1 at 286K
Thermal Expansion Coefficient (CTE)	18.1 x 10-6 /C at 273K
Knoop Hardness	82 with 500g indenter (kg/mm2)
Specific Heat Capacity	410 J/(kg.K)
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 (3900 psi)
Poisson Ratio	0.343
Chemical Properties
Solubility	0.0017 g in 100g water at 23°C
Molecular Weight	175.36 g/mole
Structure	Cubic Crystal
Cleavage Plane	(111)

Laser Crystals