Anomalous energy pathway of vacancy migration and self-diffusion in hcp Ti

Research output: Contribution to journalArticle

29 Citations (Scopus)

Abstract

An anomalous energy pathway with energetically equivalent double saddle points for vacancy mediated self-diffusion within an hcp-Ti basal plane is unveiled by density functional theory. Examination of migration pathway and phonon force constants suggests that the migrating atom tries to follow the bcc-hcp phase transition via the Burgers shear deformation. We propose that the formed energy local minimum with a bcc-like atomic environment between the two saddle points originates from the existence of high-temperature bcc phase and is a feature of Group IV hcp metals with bcc-hcp phase transition. Computed diffusion coefficients are in favorable accord with experiments for hcp Ti.

Original languageEnglish (US)
Article number224104
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume83
Issue number22
DOIs
StatePublished - Jun 17 2011

Fingerprint

saddle points
Vacancies
Phase transitions
Shear deformation
Density functional theory
diffusion coefficient
examination
Metals
density functional theory
shear
Atoms
energy
metals
atoms
Experiments
Temperature

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

@article{28862b26872c4442986da6345000f59a,
title = "Anomalous energy pathway of vacancy migration and self-diffusion in hcp Ti",
abstract = "An anomalous energy pathway with energetically equivalent double saddle points for vacancy mediated self-diffusion within an hcp-Ti basal plane is unveiled by density functional theory. Examination of migration pathway and phonon force constants suggests that the migrating atom tries to follow the bcc-hcp phase transition via the Burgers shear deformation. We propose that the formed energy local minimum with a bcc-like atomic environment between the two saddle points originates from the existence of high-temperature bcc phase and is a feature of Group IV hcp metals with bcc-hcp phase transition. Computed diffusion coefficients are in favorable accord with experiments for hcp Ti.",
author = "Shunli Shang and Hector, {L. G.} and Yi Wang and Zi-kui Liu",
year = "2011",
month = "6",
day = "17",
doi = "10.1103/PhysRevB.83.224104",
language = "English (US)",
volume = "83",
journal = "Physical Review B-Condensed Matter",
issn = "1098-0121",
publisher = "American Physical Society",
number = "22",

}

Anomalous energy pathway of vacancy migration and self-diffusion in hcp Ti. / Shang, Shunli; Hector, L. G.; Wang, Yi; Liu, Zi-kui.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 83, No. 22, 224104, 17.06.2011.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Anomalous energy pathway of vacancy migration and self-diffusion in hcp Ti

AU - Shang, Shunli

AU - Hector, L. G.

AU - Wang, Yi

AU - Liu, Zi-kui

PY - 2011/6/17

Y1 - 2011/6/17

N2 - An anomalous energy pathway with energetically equivalent double saddle points for vacancy mediated self-diffusion within an hcp-Ti basal plane is unveiled by density functional theory. Examination of migration pathway and phonon force constants suggests that the migrating atom tries to follow the bcc-hcp phase transition via the Burgers shear deformation. We propose that the formed energy local minimum with a bcc-like atomic environment between the two saddle points originates from the existence of high-temperature bcc phase and is a feature of Group IV hcp metals with bcc-hcp phase transition. Computed diffusion coefficients are in favorable accord with experiments for hcp Ti.

AB - An anomalous energy pathway with energetically equivalent double saddle points for vacancy mediated self-diffusion within an hcp-Ti basal plane is unveiled by density functional theory. Examination of migration pathway and phonon force constants suggests that the migrating atom tries to follow the bcc-hcp phase transition via the Burgers shear deformation. We propose that the formed energy local minimum with a bcc-like atomic environment between the two saddle points originates from the existence of high-temperature bcc phase and is a feature of Group IV hcp metals with bcc-hcp phase transition. Computed diffusion coefficients are in favorable accord with experiments for hcp Ti.

UR - http://www.scopus.com/inward/record.url?scp=79961144308&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=79961144308&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.83.224104

DO - 10.1103/PhysRevB.83.224104

M3 - Article

AN - SCOPUS:79961144308

VL - 83

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 1098-0121

IS - 22

M1 - 224104

ER -