ZnSe Crystals 

Simple description：

Zinc selenide (ZnSe) is an important inorganic compound composed of selenium and zinc elements. Its molecular formula is ZnSe, with a molecular weight of approximately 144.33 (or 144.369, depending on the source). ZnSe has a high melting point, usually exceeding 1000℃ (some sources indicate a melting point of 1500℃, while others suggest 1100℃, which may be related to preparation methods and purity). ZnSe crystals exhibit a light yellow hexagonal shape with a density of 5.42g/cm³.

Detailed Description：

ZnSe is insoluble in water but soluble in inorganic acids such as hydrochloric acid. When heated to a certain temperature in air, it oxidizes to selenium dioxide and zinc oxide. ZnSe has a direct bandgap structure and is a luminescent material in compound semiconductors that can emit a series of visible lights ranging from yellow to blue, making it suitable for the preparation of high-efficiency light-emitting diodes. Additionally, ZnSe has an intrinsic transmittance of up to 70% in the 8~14μm infrared band, making it an important infrared optical material.

ZnSe materials have high resistance to thermal shock and a wide transmission range, extending from 0.5 micrometers to 19 micrometers (some sources indicate a transmission range of 0.5~15μm). Therefore, ZnSe is often used to make lenses and windows for carbon dioxide lasers, as well as for manufacturing infrared-transparent materials and infrared optical instruments.

Advantages：

1. High Light Transmittance: ZnSe crystals exhibit high transparency in the visible to far-infrared regions, with a wide transmission range, effectively reducing light loss and enhancing the performance of optical systems.
2. High Thermal Stability: ZnSe crystals have high resistance to thermal shock and can maintain stable performance at high temperatures, without susceptible to thermal deformation or thermal expansion.
3. Excellent Mechanical Properties: ZnSe crystals have relatively high hardness (although slightly lower than certain materials such as ZnS) and are resistant to scratching, able to withstand certain mechanical stresses.
4. Wide Bandgap Characteristics: ZnSe crystals have a large bandgap width, exhibiting unique advantages in the manufacture of photoelectric detectors, photovoltaic devices, and other semiconductor equipment.
5. Tunable Optical and Electrical Properties: The optical and electrical properties of ZnSe crystals can be adjusted by altering preparation conditions and doping methods to meet different application requirements.
6. Ease of Processing: ZnSe crystals can be easily processed into various shapes and sizes of optical elements, such as lenses and window plates, facilitating their application in optical systems.
7. Chemical Inertia: ZnSe crystals have stable chemical properties and are not prone to reacting with other substances, maintaining stable performance in harsh environments.

Application fields：

1. Infrared Optical Materials: ZnSe crystals are the substrate of infrared optical materials and are the preferred material for infrared lenses, laser windows, infrared thermographic cameras, and high-power CO2 lasers. Due to their wide transmission range (0.5~15μm) and high sensitivity to infrared radiation, ZnSe crystals are ideal for manufacturing infrared-transparent materials and infrared optical instruments, such as optical telescopes, microscopes, and spectroscopes.
2. Photoelectric Modulators: ZnSe crystals are the basic material for photoelectric modulators and can be used to manufacture high-speed photoelectric modulators to meet the needs of the optical communication field.
3. Semiconductor Lasers: ZnSe crystals can serve as the substrate for semiconductor lasers, improving the performance of the lasers. Their excellent physical and chemical properties make them ideal materials for blue light semiconductor lasers, photoelectric detectors, nonlinear optical devices, waveguide modulators, and other equipment.
4. Imaging Devices: The optical properties of ZnSe crystals make them suitable for manufacturing imaging devices, providing high-quality optical elements for image acquisition and processing.
5. Other Applications: ZnSe crystals are also widely used in astronomy, medical instruments, infrared night vision, and other fields. Additionally, due to their stable chemical properties and resistance to reacting with other substances, ZnSe crystals are also commonly used as chemically inert materials.

Parameter：

Parameter Name	Value
Chemical Formula	ZnSe
Molar Mass	144.35 g/mol
Density	5.264~5.27 g/cm³
Crystal System	Cubic (zinc blende structure), Hexagonal (wurtzite structure)
Lattice Constants	a=0.56676 nm (cubic); a=0.398 nm, c=0.653 nm (hexagonal)
Melting Point	Approximately 1450~1517 ℃
Hardness	105~250 kg/mm² (may vary depending on testing methods and conditions)
Thermal Expansion Coefficient	7.1×10^-6 /K
Thermal Conductivity	0.16~0.0015 W/(cm·K) (may vary under different conditions)
Refractive Index	Varies with wavelength, typically between 2.4~2.5
Transmission Wavelength Range	0.5~19 μm
Maximum Transmittance	≥70.5% (under specific wavelengths and conditions)
Electron Mobility	1×10^-3 cm²/(V·s) (at room temperature)
Hole Mobility	1.6×10^-3 cm²/(V·s) (at room temperature)
Bandgap Width	Approximately 2.67 eV (at room temperature)