Lithium Fluoride is used for windows, prisms, and lenses in the vacuum UV, UV, visible and infrared where desired transmission is in the 0.104µm - 7µm range. Modest precautions should be taken against moisture and high energy radiation damage. LiF is sensitive to thermal shock. Irradiation produces color centers. The material can be cleaved. VUV grade is available.

Optical property
Crystal Class	Cubic
Density at 20°C ,g/cm3	2.60
Thermal Conductivity  W/(mk)at 314K	11.3
Thermal Expansion 1K at 300K	34.4X10-6
Reflection loss,% for tow surfaces at 4 µm	4.4
Apparent Elastic Limit.MPa	11.2
Lattice Constant,Å	4.03
Dielectric Constant for 102-1010Hz at 298K	9.0
Melting Point,K	1140
Specific Heat,cal/(gK)at 283K	0.37
Debye Temperature,K	732
Knoop Hardness,kg/mm2	100
Young's Modulus,GPa	64.77
Shear Modulus,Gpa	55.12
Bluk Modulus,GPa	62.0
Poisson's Ratio	0.326
Bandgap,eV	13.6
Water Solubility	0.27

Refractive Index
Wevelength (µm)	n	Wevelength (µm)	n
0.20	1.44	0.60	1.39
0.22	1.43	1.75	1.38
0.24	1.42	2.75	1.37
0.29	1.41	3.40	1.36
0.39	1.40