Ab initio studies of ternary semiconductor BeB2C2

作者：Yan, Haiyan^*; Zhang, Meiguang; Wei, Qun; Guo, Ping

来源：Computational Materials Science, 2013, 68: 174-180.

DOI：10.1016/j.commatsci.2012.10.013

• Beryllium diboride dicarbide
• Mechanical properties
• Electronic structure
• Thermodynamic properties

First principles calculations are performed to investigate the structural, mechanical, electronic, and thermodynamic properties of BeB2C2. Our calculated lattice parameters are in good agreement with the experimental data. Orthorhombic BeB2C2 phase is found to be mechanically stable at ambient pressure. The Young's modulus and shear modulus as a function of crystal orientation for the BeB2C2 have been systematically investigated. Further mechanical properties demonstrated that BeB2C2 is strongly prone to brittle and possesses high Vickers hardness of 26.5-28.6 GPa. Density of states and electron topological analysis show that chemical bonding among Be, B, and C atoms in BeB2C2 is a complex mixture of covalent and ionic characters. Based on the quasi-harmonic Debye model, the dependence of Debye temperature, Gruneisen parameter, heat capacity, and thermal expansion coefficient on the temperature and pressure are systematically explored in the whole pressure range from 0 to 20 GPa and temperature range from 0 to 1200 K.

• 出版日期2013-2
• 单位西北大学; 西安电子科技大学; 宝鸡文理学院