新型超硬正交BN同素异形体的第一性原理研究

应用第一性原理计算,提出一种具有正交结构的BN化合物(O-BN),空间群为Pbam.计算结果表明:O-BN具有较强的抗压缩性和较大的体弹模量(397.38 GPa),其理论硬度值可达到65.10 GPa.同时,与先前理论提出的BN同素异形体相比,O-BN的能量更为稳定.理想拉伸强度计算进一步表明O-BN是一种潜在的超硬材料.我们的研究结果为实验上合成BN化合物起到了重要的理论指导作用.

First-principles Study of a Novel Superhard Orthorhombic BN Allotrope

A novel superhard orthorhombic allotrope of boron nitride （O-BN） with the space group of Pbam has been predicted using first-principles calculations. Our results revealed that O-BN simultaneously posses incompressible with a high bulk modulus of 397.38 GPa, and superhard properties with a high Vickers hardness of 65.10 GPa. Furthermore, the ideal strength calculations indicate that O-BN is a potential superhard material. Our results play an important theoretical role in guiding the experimental synthesis of BN compounds.