Regulation of Te atomic vacancy defects in the intrinsic magnetic topological insulator $$\hbox {MnBi}_{{6}}\hbox {Te}_{{10}}$$

Binding energies ([Formula: see text], geometric and electronic structures for [[Formula: see text]](O/[[Formula: see text]]) additions of O atom on ([Formula: see text])([Formula: see text] − 10) single-walled carbon nanotubes with di-vacancies are studied using a GGA-PBE method, and defect curvature ([Formula: see text]) is used to predict reactivities of different C—C bonds at defect area. Calculated results show that the C—C bonds can be divided into two types: broken C—C bonds corresponding to adducts with a C—O—C configuration structure and unbroken C—C bonds corresponding to adducts with a closed-3MR structure. [Formula: see text] of O/[[Formula: see text]] additions for the adduct with the C—O—C configuration structure monotonously increases with the increase of [Formula: see text] in any ([Formula: see text],0)([Formula: see text]) tube and decreases with the increase of [Formula: see text] in ([Formula: see text],0)([Formula: see text], 7, 10) tubes. Besides the fact that [Formula: see text] value is mainly determined by the defect curvature, it is also affected by band gaps, bonding characteristic of C—C bonds in the highest occupied molecular orbital (HOMO) and geometric structures. The study would provide a theoretical basis for surface modifications of carbon nanotubes with atomic vacancy defects.

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The Effects of Random Porosities in Resonant Frequencies of Graphene Based on the Monte Carlo Stochastic Finite Element Model

International Journal of Molecular Sciences ◽

10.3390/ijms22094814 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4814

Author(s):

Liu Chu ◽

Jiajia Shi ◽

Yue Yu ◽

Eduardo Souza De Cursi

Keyword(s):

Finite Element ◽

Monte Carlo ◽

Finite Element Model ◽

Element Model ◽

Working Environment ◽

Probability Density Distribution ◽

Resonant Frequencies ◽

Vacancy Defects ◽

Porous Graphene ◽

Atomic Vacancy

With the distinguished properties in electronics, thermal conductivity, optical transparence and mechanics, graphene has a powerful potential in nanosensors, nano-resonators, supercapacitors, batteries, etc. The resonant frequency of graphene is an important factor in its application and working environment. However, the random dispersed porosities in graphene evidently change the lattice structure and destroy the integrity and geometrical periodicity. This paper focuses on the effects of random porosities in resonant frequencies of graphene. Monte Carlo simulation is applied to propagate the porosities in the finite element model of pristine graphene. The statistical results and probability density distribution of porous graphene with atomic vacancy defects are computed based on the Monte Carlo finite element model. The results of porous graphene with atomic vacancy defects are compared and discussed with the results of graphene with bond vacancy defects. The enhancement effects of atomic vacancy defects are confirmed in porous graphene. The influences of atomic vacancy defects on displacement and rotation vector sums of porous graphene are more concentrated in local places.

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Molecular Dynamics Study on the Interface Properties of the Ternary Boride Cladding Materials with Atomic Vacancy Defects

DEStech Transactions on Engineering and Technology Research ◽

10.12783/dtetr/apetc2017/11033 ◽

2017 ◽

Author(s):

Junru Yang ◽

Minglan Wang ◽

Haitao Feng

Keyword(s):

Molecular Dynamics ◽

Interface Properties ◽

Vacancy Defects ◽

Ternary Boride ◽

Atomic Vacancy

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Influence of Atomic Defect on the Deformation Properties of Nanowires Subjected to Uniaxial Tension

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.873.139 ◽

2013 ◽

Vol 873 ◽

pp. 139-146

Author(s):

Fen Ying Wang ◽

Wei Sun ◽

Yan Feng Dai ◽

Yi Wang Chen ◽

Jian Wei Zhao ◽

...

Keyword(s):

Single Layer ◽

Gold Nanowires ◽

Brittle Deformation ◽

Vacancy Defects ◽

Deformation Properties ◽

Atomic Vacancy ◽

Dynamics Simulations ◽

Mechanical Strengths ◽

Crystalline Plane ◽

Oriented Single Crystal

Atomic defects play an important role in the brittle deformation of nanowires at low temperatures. With molecular dynamics simulations, we study the influence of vacancy defects on the deformation and breaking behaviors of [10 oriented single-crystal gold nanowires at 50 and 150 K. The size of the nanowire is 10a × 10a × 30a (a stands for lattice constant, 0.408 nm for gold). It is shown that good crystalline structure appears in the whole deformation process, and it is in a brittle way at low temperature. The nanowire breaking behavior is sensitive to atomic vacancies when the atomic vacancy ratio is 1% in single-layer crystalline plane. Within the limitation of vacancy-induced breaking of the nanowire, the mechanical strengths increase under atomic vacancies. However, it decreases with the defect ratio increasing.

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The Fingerprints of Resonant Frequency for Atomic Vacancy Defect Identification in Graphene

Nanomaterials ◽

10.3390/nano11123451 ◽

2021 ◽

Vol 11 (12) ◽

pp. 3451

Author(s):

Liu Chu ◽

Jiajia Shi ◽

Eduardo Souza de Cursi

Keyword(s):

Resonant Frequency ◽

Element Model ◽

Vacancy Defect ◽

Supplementary Information ◽

Experimental Conditions ◽

Defect Identification ◽

Vacancy Defects ◽

Detection And Identification ◽

Atomic Vacancy ◽

Defects Identification

The identification of atomic vacancy defects in graphene is an important and challenging issue, which involves inhomogeneous spatial randomness and requires high experimental conditions. In this paper, the fingerprints of resonant frequency for atomic vacancy defect identification are provided, based on the database of massive samples. Every possible atomic vacancy defect in the graphene lattice is considered and computed by the finite element model in sequence. Based on the sample database, the histograms of resonant frequency are provided to compare the probability density distributions and interval ranges. Furthermore, the implicit relationship between the locations of the atomic vacancy defects and the resonant frequencies of graphene is established. The fingerprint patterns are depicted by mapping the locations of atomic vacancy defects to the resonant frequency magnitudes. The geometrical characteristics of computed fingerprints are discussed to explore the feasibility of atomic vacancy defects identification. The work in this paper provides meaningful supplementary information for non-destructive defect detection and identification in nanomaterials.

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