Tsetseris L, Kalfagiannis N, Logothetidis S, Pantelides S T
Department of Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece.
Phys Rev Lett. 2007 Sep 21;99(12):125503. doi: 10.1103/PhysRevLett.99.125503. Epub 2007 Sep 19.
Transition-metal nitrides (TMN) have exceptional stability, which underlies their use in various applications. Here, we study the role of N point defects on the stability of prototype TMNs using first-principles calculations. We find that distinct regimes for TMN changes relate to specific atomic-scale mechanisms, namely, diffusion of N interstitials (I(N)), of I(N) pairs, and of N vacancies. The activation of these processes occurs sequentially as the temperature is raised in a range of several hundreds of degrees, accounting for observed TMN changes under widely different conditions.
过渡金属氮化物（TMN）具有卓越的稳定性，这是它们在各种应用中得以使用的基础。在此，我们使用第一性原理计算研究了N点缺陷对典型TMN稳定性的作用。我们发现，TMN变化的不同机制与特定的原子尺度机制相关，即N间隙原子（I(N)）、I(N)对以及N空位的扩散。随着温度在几百摄氏度的范围内升高，这些过程依次被激活，这解释了在广泛不同条件下观察到的TMN变化。
