TY - JOUR
T1 - A first-principles study of self-diffusion coefficients of fcc Ni
AU - Hargather, Chelsey Z.
AU - Shang, Shun Li
AU - Liu, Zi Kui
AU - Du, Y.
N1 - Funding Information:
This work was funded by the Office of Naval Research (ONR) under contract No. N0014-07-1-0638 and the Center for Computational Materials Design (CCMD), a joint National Science Foundation (NSF) Industry/University Cooperative Research Center at Penn State (IIP-1034965) and Georgia Tech (IIP-1034968). First-principles calculations were carried out in part on the LION clusters at the Pennsylvania State University supported by the Materials Simulation Center and the Research Computing and Cyberinfrastructure unit at The Pennsylvania State University, and in part by the high performance computing resources at ERDC as part of the Department of Defense High Performance Computing Modernization Program. We thank ONR program manager David Shifler for his support and encouragement. The authors would like to thank M. Epler and A. D. Patel from Carpenter Technology Corporation and Paul Mason from Thermo-Calc AB for mentoring the CCMD project. The authors also would like to thank the support from National Natural Science Foundation of China (NSFC) with the Grant No. 51028101 .
PY - 2014/4/15
Y1 - 2014/4/15
N2 - Self-diffusion coefficients for fcc Ni are obtained as a function of temperature by first-principles calculations based on density functional theory within the local density approximation. To provide the minimum energy pathway and the associated saddle point structures of an elementary atomic jump, the nudged elastic band method is employed. Two magnetic settings, ferromagnetic and non-magnetic, and two vibrational contribution calculation methods, the phonon supercell approach and the Debye model, create four calculation settings for the self-diffusion coefficient in nickel. The results from these four methods are compared to each other and presented with the known experimental data. The use of the Debye model in lieu of the phonon supercell approach is shown to be a viable and computationally time saving alternative for the finite temperature thermodynamic properties. Consistent with other observations in the literature, the use of the phonon supercell approach for the calculation of the finite temperature thermodynamic properties within the LDA results in an underestimation of the diffusion coefficient with respect to experimental data. The calculated Ni self-diffusion coefficients for all four conditions in the present work are compared to a statistical consensus analysis previously performed on all known experimental self-diffusion data. With the exception of the NM phonon setting, the other three conditions fall within the 95% confidence interval for the consensus analysis.
AB - Self-diffusion coefficients for fcc Ni are obtained as a function of temperature by first-principles calculations based on density functional theory within the local density approximation. To provide the minimum energy pathway and the associated saddle point structures of an elementary atomic jump, the nudged elastic band method is employed. Two magnetic settings, ferromagnetic and non-magnetic, and two vibrational contribution calculation methods, the phonon supercell approach and the Debye model, create four calculation settings for the self-diffusion coefficient in nickel. The results from these four methods are compared to each other and presented with the known experimental data. The use of the Debye model in lieu of the phonon supercell approach is shown to be a viable and computationally time saving alternative for the finite temperature thermodynamic properties. Consistent with other observations in the literature, the use of the phonon supercell approach for the calculation of the finite temperature thermodynamic properties within the LDA results in an underestimation of the diffusion coefficient with respect to experimental data. The calculated Ni self-diffusion coefficients for all four conditions in the present work are compared to a statistical consensus analysis previously performed on all known experimental self-diffusion data. With the exception of the NM phonon setting, the other three conditions fall within the 95% confidence interval for the consensus analysis.
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U2 - 10.1016/j.commatsci.2014.01.003
DO - 10.1016/j.commatsci.2014.01.003
M3 - Article
AN - SCOPUS:84893832318
VL - 86
SP - 17
EP - 23
JO - Computational Materials Science
JF - Computational Materials Science
SN - 0927-0256
ER -