Ab initio molecular dynamics simulations of ion-solid interactions in zirconate pyrochlores

doi:10.1016/j.actamat.2015.01.019

Title: Ab initio molecular dynamics simulations of ion-solid interactions in zirconate pyrochlores

Abstract

In this paper, an ab initio molecular dynamics method is employed to study low energy recoil events in zirconate pyrochlores (A₂Zr₂O₇, A = La, Nd and Sm). It shows that both cations and anions in Nd₂Zr₂O₇ and Sm₂Zr₂O₇ are generally more likely to be displaced than those in La₂Zr₂O₇. The damage end states mainly consist of Frenkel pair defects, and the Frenkel pair formation energies in Nd₂Zr₂O₇ and Sm₂Zr₂O₇ are lower than those in La₂Zr₂O₇. These results suggest that the order–disorder structural transition more easily occurs in Nd₂Zr₂O₇ and Sm₂Zr₂O₇ resulting in a defect-fluorite structure, which agrees well with experimental observations. Our calculations indicate that oxygen migration from 48f and 8b to 8a sites is dominant under low energy irradiation. A number of new defects, including four types of cation Frenkel pairs and six types of anion Frenkel pairs, are revealed by ab initio molecular dynamics simulations. The present findings may help to advance the fundamental understanding of the irradiation response behavior of zirconate pyrochlores.

Authors:

Xiao, Haiyan Y. ^[1]; Weber, William J. ^[2]; Zhang, Yanwen ^[3]; Zu, X. T. ^[1]

University of Electronic Science and Technology of China, Chengdu (China)
Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)

Publication Date:: 2015-01-31

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:: 1265303

Alternate Identifier(s):: OSTI ID: 1250964

Grant/Contract Number:: AC05-00OR22725

Resource Type:: Accepted Manuscript

Journal Name:: Acta Materialia

Additional Journal Information:: Journal Volume: 87; Journal ID: ISSN 1359-6454

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; 38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY; Computer simulation; Zirconate pyrochlores; Radiation effects; Charge transfer

Citation Formats


                    Xiao, Haiyan Y., Weber, William J., Zhang, Yanwen, and Zu, X. T. Ab initio molecular dynamics simulations of ion-solid interactions in zirconate pyrochlores.  United States: N. p., 2015. 
        Web.  doi:10.1016/j.actamat.2015.01.019.

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                    Xiao, Haiyan Y., Weber, William J., Zhang, Yanwen, & Zu, X. T. Ab initio molecular dynamics simulations of ion-solid interactions in zirconate pyrochlores.  United States.  doi:10.1016/j.actamat.2015.01.019.

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                    Xiao, Haiyan Y., Weber, William J., Zhang, Yanwen, and Zu, X. T. Sat .  
        "Ab initio molecular dynamics simulations of ion-solid interactions in zirconate pyrochlores".  United States.  doi:10.1016/j.actamat.2015.01.019.  https://www.osti.gov/servlets/purl/1265303.

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@article{osti_1265303,

  title        = {Ab initio molecular dynamics simulations of ion-solid interactions in zirconate pyrochlores},

  author       = {Xiao, Haiyan Y. and Weber, William J. and Zhang, Yanwen and Zu, X. T.},

  abstractNote = {In this paper, an ab initio molecular dynamics method is employed to study low energy recoil events in zirconate pyrochlores (A2Zr2O7, A = La, Nd and Sm). It shows that both cations and anions in Nd2Zr2O7 and Sm2Zr2O7 are generally more likely to be displaced than those in La2Zr2O7. The damage end states mainly consist of Frenkel pair defects, and the Frenkel pair formation energies in Nd2Zr2O7 and Sm2Zr2O7 are lower than those in La2Zr2O7. These results suggest that the order–disorder structural transition more easily occurs in Nd2Zr2O7 and Sm2Zr2O7 resulting in a defect-fluorite structure, which agrees well with experimental observations. Our calculations indicate that oxygen migration from 48f and 8b to 8a sites is dominant under low energy irradiation. A number of new defects, including four types of cation Frenkel pairs and six types of anion Frenkel pairs, are revealed by ab initio molecular dynamics simulations. The present findings may help to advance the fundamental understanding of the irradiation response behavior of zirconate pyrochlores.},

  doi          = {10.1016/j.actamat.2015.01.019},

  journal      = {Acta Materialia},

  number       = ,

  volume       = 87,

  place        = {United States},

  year         = {2015},

  month        = {1}

}

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DOI: 10.1016/j.actamat.2015.01.019

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Works referencing / citing this record:

Investigations of atomic disorder and grain growth kinetics in polycrystalline La2Zr2O7
journal, May 2019

Panghal, Asha; Kulriya, Pawan K.; Kumar, Yogendra
Applied Physics A, Vol. 125, Issue 6
DOI: 10.1007/s00339-019-2720-8

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Title: Ab initio molecular dynamics simulations of ion-solid interactions in zirconate pyrochlores

Abstract

Citation Formats

Investigations of atomic disorder and grain growth kinetics in polycrystalline La2Zr2O7 journal, May 2019

Investigations of atomic disorder and grain growth kinetics in polycrystalline La2Zr2O7
journal, May 2019