LiF

Chemical formula: LiF

Lithium fluoride crystals show excellent transmittance in the vacuum ultraviolet region.

It is used for visible light and 0.104 μ m - 7 μ M infrared window, prism and lens.

Lithium fluoride crystals are sensitive to thermal shock and are affected by atmospheric water molecules at 400 ° C.

In addition, irradiation produces color centers. Appropriate precautions shall be taken to prevent moisture and high-energy radiation damage. Lithium fluoride softens at 600 ° C and can be slightly bent into a radius plate. The material can be cut along (100) and less commonly (110). Although the optical properties are good, the structure is imperfect and cutting is difficult. High quality lithium fluoride is usually grown by improved Bridgeman technology.

Lithium fluoride shows good optical properties. It can be used for windows, prisms and lenses in vacuum, ultraviolet, visible and infrared.

Due to its symmetrical lattice structure, lithium fluoride can also be used as an X-ray diffraction device.

Lithium fluoride crystal (LIF) belongs to cubic crystal system with (100) cleavage plane, which has excellent optical properties, especially in deep ultraviolet band.

Main Parameter

Growth methods: Czochralski method and Bridgeman method

Crystal structure: tripartite

Lattice constant: a = 4.026 Å

Color and appearance: colorless and transparent

Density: 2.60 g / cm3

Melting point: 870 ℃

Mohs hardness: 4mohs

Coefficient of thermal expansion: 37.0 x 10-6 / ℃ @ 0-100 ℃

Transmission range: 0.105 ~ 6 μ m

Dielectric constant: 9.0 @ 25 ℃, f = 100.. 109hz

Thermal conductivity: 11.3w / m.k @ 41 ℃

Specific heat: 1562j / kg. K

Refractive index: 1.37327 @ 2.5 μ m; 1.624 @0.121 μ m

Reflection loss: 4.4% (4.0 μ m）

Young's modulus: 64.79gpa

Shear modulus: 55.14gpa

Bulk modulus: 62.03gpa

Breaking modulus: 10.8mpa

Elastic coefficient: C11 = 112; C12=45.6; C44=63.2GPa

Water solubility: 0.27g/100g @ 18 ℃

Crystal cleavage surface: < 100 >

Crystal direction: < 100 >, < 111 >

Crystal plane orientation accuracy: ± 0.5 °

Edge orientation accuracy: ± 1 °

Chamfered wafer: special direction can be customized according to customer requirements

Size (special size can be customized according to customer requirements)

ten × ten × 1.0mm、10 × five × 1.0mm、10 × ten × 0.5mm、10 × five × 0.5mm, etc

dia12 × 4.0mm、dia12 × 4.0mm, etc

Polishing: single side polishing, double side polishing, etc