Ideal Strengths and Bonding Properties of PuO2 under Tension

• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2011,（4）
• 页码范围: 178-181
• 页数: 4页
• 语种: 英文
• DOI: 10.1088/0256-307X/28/4/047101

摘要

We perform a first-principles computational tensile test on Pu02 based on density-functional theory within a local density approximation(LDA)+U formalism to investigate its structural, mechanical, magnetic and intrinsic bonding properties in four representative directions:[001], [100], [110] and [111].The stress-strain relations show that the ideal tensile strengths in the four directions are 81.2, 80.5, 28.3 and 16.8 GPa at strains of 0.36, 0.36,0.22 and 0.18, respectively.The [001]and [100]directions are prominently stronger than the other two directions since more Pu-0 bonds participate in the pulling process.By charge and density of state analysis along the[001]direction,we find that the strong mixed ioni%ovalent character of the Pu-0 bond is weakened by tensile strain and PuO2 will exhibit an insulator-to-metal transition after tensile stresses exceeding about 79 GPa.