Temperature-dependent properties of transition metal nitrides and carbides via equilibrium and non-equilibrium quantum molecular dynamics
Title: |
Temperature-dependent properties of transition metal nitrides and carbides via equilibrium and non-equilibrium quantum molecular dynamics |
DNr: |
SNIC 2015/1-393 |
Project Type: |
SNIC Medium Compute |
Principal Investigator: |
Valeriu Chirita <vio@ifm.liu.se> |
Affiliation: |
Linköpings universitet |
Duration: |
2015-11-01 – 2016-11-01 |
Classification: |
20501 |
Keywords: |
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Abstract
We use density-functional-based ab initio molecular dynamics (AIMD) to determine the electronic and mechanical properties of transition metal nitrides and carbides as a function of temperature.
Since lattice vibrations strongly affect structural stability [1], lattice ordering, and reaction rates at finite temperatures [2,3], AIMD is the most reliable computational tool in determining material properties and revealing non-intuitive
reaction pathways at finite temperatures [2,4]. Given the limitations on the time-scales accessible via highly computationally-demanding AIMD simulations, a non-equilibrium technique (accelerated AIMD) that we have recently developed [5] is employed to efficiently achieve accurate quantitative evaluation of the rate of rare events, such as dislocation glide and point-defect formation and migration.
[1] A.B. Mei, O. Hellman, N. Wireklint, C.M. Schlepütz,
D.G. Sangiovanni, B. Alling, A. Rockett, L. Hultman, I.
Petrov, J.E. Greene Physical Review B 91, (2015) 054101
[2] D. G. Sangiovanni, B. Alling, P. Steneteg, L. Hultman,
I. A. Abrikosov Physical Review B 91, (2015) 054301
[3] D.G. Sangiovanni, D. Edström, L. Hultman, I. Petrov, J.E.
Greene, V. Chirita Surface Science, 627 (2014) 34
[4] D.G.Sangiovanni, D. Edström, L. Hultman, I. Petrov, J.E.
Greene, V. Chirita Surface Science, 624 (2014) 25
[5] D.G. Sangiovanni, O. Hellman, B. Alling, I.A. Abrikosov
Efficient and accurate determination of lattice-vacancy
diffusion coefficients via nonequilibrium ab initio
molecular dynamics arXiv:1509.04487 (submitted)