TY  - SER
AU  - Sangiovanni,D.G.
AU  - Steneteg,P.
AU  - Hultman,Lars
AU  - Abrikosov,Igor A.
AU  - Alling,B.
TI  - Nitrogen vacancy, self-interstitial diffusion, and Frenkel-pair formation/dissociation in B1 TiN studied by ab initio and classical molecular dynamics with optimized potentials
KW  - Френкеля дефекты
KW  - нитрид титана
KW  - тонкие пленки
KW  - ab initio расчеты
KW  - молекулярная динамика
KW  - статьи в журналах
N1  - Библиогр.: 95 назв
N2  - We use ab initio and classical molecular dynamics (AIMD and CMD) based on the modified embedded-atom method (MEAM) potential to simulate diffusion of N vacancy and N self-interstitial point defects in B1 TiN. TiN MEAM parameters are optimized to obtain CMD nitrogen point-defect jump rates in agreement with AIMD predictions, as well as an excellent description of TiNx (∼0.7 < x  1) elastic, thermal, and structural properties. We determine N dilute-point-defect diffusion pathways, activation energies, attempt frequencies, and diffusion coefficients as a function of temperature. In addition, the MD simulations presented in this paper reveal an unanticipated atomistic process, which controls the spontaneous formation of N self-interstitial/N vacancy (NI/NV) pairs (Frenkel pairs), in defect-free TiN. This entails that the N lattice atom leaves its bulk position and bonds to a neighboring N lattice atom. In most cases, Frenkel-pair NI and NV recombine within a fraction of ns; ∼50% of these processes result in the exchange of two nitrogen lattice atoms (N−NExc). Occasionally, however, Frenkel-pair N-interstitial atoms permanently escape from the anion vacancy site, thus producing unpaired NI and NV point defects
UR  - http://vital.lib.tsu.ru/vital/access/manager/Repository/vtls:000624927
ER  -