Uberuaga B P, Smith R, Cleave A R, Montalenti F, Henkelman G, Grimes R W, Voter A F, Sickafus K E
Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Phys Rev Lett. 2004 Mar 19;92(11):115505. doi: 10.1103/PhysRevLett.92.115505.
We study radiation-damage events in MgO on experimental time scales by augmenting molecular dynamics cascade simulations with temperature accelerated dynamics, molecular statics, and density functional theory. At 400 eV, vacancies and mono- and di-interstitials form, but often annihilate within milliseconds. At 2 and 5 keV, larger clusters can form and persist. While vacancies are immobile, interstitials aggregate into clusters (In) with surprising properties; e.g., an I4 is immobile, but an impinging I2 can create a metastable I6 that diffuses on the nanosecond time scale but is stable for years.
我们通过温度加速动力学、分子静力学和密度泛函理论增强分子动力学级联模拟，在实验时间尺度上研究氧化镁中的辐射损伤事件。在400电子伏特时，空位以及单间隙和双间隙形成，但通常会在几毫秒内湮灭。在2千电子伏特和5千电子伏特时，可以形成更大的团簇并持续存在。虽然空位是不动的，但间隙原子聚集成具有惊人特性的团簇（In）；例如，一个I4是不动的，但一个撞击的I2可以产生一个亚稳态的I6，它在纳秒时间尺度上扩散，但能稳定数年。
