Calculation of point defects in rutile TiO<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mrow /><mml:mn>2</mml:mn></mml:msub></mml:math>by the screened-exchange hybrid functional

Lee, Hsin‐Yi; Clark, S. J.; Robertson, John

doi:10.1103/physrevb.86.075209

Cited by 96 publications

(66 citation statements)

References 73 publications

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“…4,5 In order to investigate the discrepancy mentioned above, various kinds of functional were tested. The functional LDA, 26,36 PBE 22,27 and sX-LDA [30][31][32][33][37][38][39][40] were used in the DFT calculation. The valence states electrons of strontium were treated as 5s 2 , 4p 6 and 3d 2 states.…”

Section: Resultsmentioning

confidence: 99%

“…It, however, catches a little attention as no one has used the functional for structural phase transition prediction but for optical, 37,38 band gap, [32][33][34]38,39 band structure and electronic density of state. [32][33][34]38,40 Therefore, this work trailblazes the use of sX-LDA to find structural transition of solids which was validated by solving long-known computational experimental disagreement.…”

Section: -6mentioning

confidence: 99%

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Existence of the β-tin structure in Sr: First evidence from computational approach

et al. 2015

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Molecular Dynamics (MD) calculation is one of the most powerful theoretical methods widely used to predict and to confirm structural phase transitions. In this work, the MD method has been used to verify phase transition from body-centered cubic (bcc) to β-tin structure, then, to the Cmcm and hexagonal close-packed (hcp) structure, respectively. The transition sequence from previous theoretical works has been confirmed. In this study, Density Functional Theory (DFT), has been used to calculate phonon dispersion to confirm the stability of β-tin and hcp phases. The long time discrepancies in transition sequence between the calculation and the experimental works has been explained by conventional DFT calculation using screened exchange local density approximation (sX-LDA). More importantly, the existence of β-tin structure is finally predicted and the transition nature of Sr has also been revealed.

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Section: Resultsmentioning

confidence: 99%

Section: -6mentioning

confidence: 99%

Existence of the β-tin structure in Sr: First evidence from computational approach

et al. 2015

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“…In order to reproduce the correct polaronic behaviors, the self-interaction of electrons must be treated properly to balance the tendency of localization versus delocalization [33][34][35][36][37][38][39][40][41][42][43][44]. Hybrid functionals [33][34][35][36][37][38][39][40] and on-site Coulomb corrections [31,32,[41][42][43][44] are two potential treatments. Using hybrid functionals, several groups of researchers have reported the co-existence of two distinct polaronic states [17,[35][36][37][38].…”

Section: Methodsmentioning

confidence: 99%

Polaronic interactions between oxygen vacancies in rutile TiO2

2017

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Oxygen vacancy-vacancy interactions in rutile TiO 2 are studied in conjunction with polaron formation trends using density functional theory calculations. It is found that polarons strongly enhance the formation of oxygen vacancies in this material, and also mediate the interactions between existing vacancies. At distances below one nanometer, two isolated and charge-neutral vacancies exhibit attractive interactions with an equilibrium distance of about 4 Ångstroms. The attractive forces between vacancies partly arise from the polaronic transfer of excess electrons to reduce the potential energy. These discoveries provide microscopic explanations to the vacancy clustering phenomena, as well as a practical approach to stabilize the polarons at arbitrary Ti atoms in TiO 2 .

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“…These results are shown in Table III. As is known for the same type of defects (V O 's) in the TiO 2 rutile, the removal of oxygen atoms from the oxide structure leaves a pair of unbound electrons [36,65]. Each of the Ti n O 2n−1 phases presents two V O 's per unit cell, therefore there are four electrons left behind.…”

Section: B Electronic and Magnetic Propertiesmentioning

confidence: 99%

TinO2n−1Magnéli phases studied using density functional theory

et al. 2014

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Defects in the rutile TiO 2 structures have been extensively studied, but the intrinsic defects of the oxygendeficient Ti n O 2n−1 phases have not been given the same amount of consideration. Those structures, known as Magnéli phases, are characterized by the presence of ordered planes of oxygen vacancies, also known as shear planes, and it has been shown that they form conducting channels inside TiO-based memristor devices. Memristors are excellent candidates for a new generation of memory devices in the electronics industry. In this paper we present density-functional-theory-based electronic structure calculations for Ti n O 2n−1 Magnéli structures using PBESol+U (0 U 5 eV) and Heyd-Scuseria-Ernzerhof functionals, showing that intrinsic defects present in these structures are responsible for the appearance of states inside the band gap, which can act as intrinsic dopants for the enhanced conductivity of TiO 2 memristive devices.

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Calculation of point defects in rutile TiO2by the screened-exchange hybrid functional

Cited by 96 publications

References 73 publications

Existence of the β-tin structure in Sr: First evidence from computational approach

Existence of the β-tin structure in Sr: First evidence from computational approach

Polaronic interactions between oxygen vacancies in rutile TiO2

TinO2n−1Magnéli phases studied using density functional theory

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