skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: A comprehensive computational study of adatom diffusion on the aluminum (1 0 0) surface

Abstract

The complexity of adatom diffusion on the Al (1 0 0) surface is reflected by the existence of several low-energy non-trivial atomic exchange or vacancy formation mechanisms involving concerted motion of several (3–7) atoms. Interestingly, these mechanisms have energy barriers lower than or comparable to that of the simple (and intuitive) hopping mechanism commonly observed on other surface facets. While prior studies mainly used classical potentials to understand diffusion processes active on Al (1 0 0) surface, we use accurate (and expensive) density functional theory (DFT) computations to estimate barriers associated with nine low-energy and non-trivial adatom diffusion mechanisms. We find that there exist several exchange mechanisms with energy barriers less than or equal to that of the trivial hop mechanism. Furthermore, several of the atomic exchange mechanisms have barriers within 0.2 eV of that of the simple hop, thereby highlighting mechanisms that can be relevant during surface/crystal growth. Our results paint a highly complex picture of the diffusion landscape on Al (1 0 0) and provide insights into how such mechanisms may contribute toward large length- and time-scale surface phenomena. The results presented in this work may also have implications for other fcc metals. Further, we show that somemore » of the commonly used interatomic potentials fail to accurately capture the details of adatom diffusion on Al (1 0 0). The presented benchmark DFT dataset can thus be utilized to parameterize/retrain such potentials.« less

Authors:
 [1];  [2];  [3];  [3];  [1]
  1. Georgia Inst. of Technology, Atlanta, GA (United States). Dept. of Materials Science & Engineering
  2. Univ. of Connecticut, Storrs, CT (United States). Dept. of Materials Science & Engineering
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Georgia Inst. of Technology, Atlanta, GA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); USDOE National Nuclear Security Administration (NNSA); National Science Foundation (NSF)
OSTI Identifier:
1503191
Report Number(s):
LA-UR-18-29653
Journal ID: ISSN 0927-0256
Grant/Contract Number:  
89233218CNA000001; 1821992
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Computational Materials Science
Additional Journal Information:
Journal Volume: 158; Journal ID: ISSN 0927-0256
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 97 MATHEMATICS AND COMPUTING; density functional theory; aluminum adatom diffusion mechanisms; computational materials science; nudged elastic band; embedded atom method

Citation Formats

Chapman, J., Batra, R., Uberuaga, B. P., Pilania, G., and Ramprasad, R. A comprehensive computational study of adatom diffusion on the aluminum (1 0 0) surface. United States: N. p., 2018. Web. doi:10.1016/j.commatsci.2018.11.032.
Chapman, J., Batra, R., Uberuaga, B. P., Pilania, G., & Ramprasad, R. A comprehensive computational study of adatom diffusion on the aluminum (1 0 0) surface. United States. doi:10.1016/j.commatsci.2018.11.032.
Chapman, J., Batra, R., Uberuaga, B. P., Pilania, G., and Ramprasad, R. Thu . "A comprehensive computational study of adatom diffusion on the aluminum (1 0 0) surface". United States. doi:10.1016/j.commatsci.2018.11.032.
@article{osti_1503191,
title = {A comprehensive computational study of adatom diffusion on the aluminum (1 0 0) surface},
author = {Chapman, J. and Batra, R. and Uberuaga, B. P. and Pilania, G. and Ramprasad, R.},
abstractNote = {The complexity of adatom diffusion on the Al (1 0 0) surface is reflected by the existence of several low-energy non-trivial atomic exchange or vacancy formation mechanisms involving concerted motion of several (3–7) atoms. Interestingly, these mechanisms have energy barriers lower than or comparable to that of the simple (and intuitive) hopping mechanism commonly observed on other surface facets. While prior studies mainly used classical potentials to understand diffusion processes active on Al (1 0 0) surface, we use accurate (and expensive) density functional theory (DFT) computations to estimate barriers associated with nine low-energy and non-trivial adatom diffusion mechanisms. We find that there exist several exchange mechanisms with energy barriers less than or equal to that of the trivial hop mechanism. Furthermore, several of the atomic exchange mechanisms have barriers within 0.2 eV of that of the simple hop, thereby highlighting mechanisms that can be relevant during surface/crystal growth. Our results paint a highly complex picture of the diffusion landscape on Al (1 0 0) and provide insights into how such mechanisms may contribute toward large length- and time-scale surface phenomena. The results presented in this work may also have implications for other fcc metals. Further, we show that some of the commonly used interatomic potentials fail to accurately capture the details of adatom diffusion on Al (1 0 0). The presented benchmark DFT dataset can thus be utilized to parameterize/retrain such potentials.},
doi = {10.1016/j.commatsci.2018.11.032},
journal = {Computational Materials Science},
issn = {0927-0256},
number = ,
volume = 158,
place = {United States},
year = {2018},
month = {11}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on November 29, 2019
Publisher's Version of Record

Save / Share: