类单晶硅结构Si(C≡C―C_6H_4―C≡C)_4新材料的力学与光学性质:第一性原理研究

基于单晶硅中Si的四面体成键特征及对其结构单元的替换修饰,我们设计了一种类单晶硅结构的新材料-C_(40)H_(16)Si_2。通过广泛的第一性原理计算,研究了这类材料的电子性质、力学性质和光学性质。计算结果表明,这种新材料具有好的热力学稳定性和机械稳定性。该材料的禁带宽度为3.32 eV,价带底和导带顶都位于Gamma点,是直接带隙宽禁带半导体材料。该材料的维氏硬度和密度非常小,不到单晶硅的十分之一,是一类低密度的柔性多孔材料。此外,该材料在紫外光区有强的吸收,有望应用于蓝绿光发光二极管。

Mechanical and Optical Properties of a Novel Diamond-Like Si(C≡C－C6H4－C≡C)4 Single-Crystalline Semiconductor: a First-Principles Study

In this work, a monocrystalline silicon-like material, C₄₀H₁₆Si₂, was designed by structural modification based on the tetrahedral bonding features of silicon. The electronic, mechanical, and optical properties of this material were explored by first-principles calculations. The obtained results revealed that this material shows high thermodynamic stability and mechanical stability. The bandgap for Si(C≡C–C₆H₄–C≡C)₄ was calculated to be 3.32 eV, and its valence and conduction bands were located at the Gamma point, indicating that this material is a direct wide-bandgap semiconductor. The Vickers hardness and density of this material were very small, less than one-tenth of that of single-crystalline silicon. The novel compound is a flexible and porous material with low density, and its strong absorption in the UV region makes it a promising semiconductor for blue and green light-emitting diodes.