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Schematic diagram showing zigzag, armchair and …

2020-5-29 · Schematic diagram showing zigzag, armchair and chiral carbon nanotubes. From: Moones Rahmandoust and Andreas Öchsner (Faculty of Mechanical Engineering, Universiti Teknologi Malaysia UTM 81310 Johor Bahru, Hohor, Malaysia),

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From zigzag to armchair: the energetic stability ...

2011-10-3 · The chiral vector, chiral angle, edge geometry, average width and the percentage of carbon atoms at the zigzag sites of these 8Z/14A-GNRs are listed in table 1. Since the number of carbon atoms at each edge is just equal to n + m , in the literature such edges are called minimal edges [ 24 , 25 ].

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A Study of Fe3O4@ Zigzag, @Armchair and @Chiral …

ABSTRACT: Fe 3 O 4 is used as a catalyst in the Haber process and in the water gas shift reaction. In this work we have investigated the physical and chemical properties of Fe 3 O 4 @ Zigzag, @Armchair and @Chiral SWCNTs compare to Fe 3 O 4 @ -Cyclodextrin in view point of chemical reaction and sensitizes. The electrical properties such as NMR Shielding, electron densities, energy densities ...

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Optimizing the thermoelectric performance of zigzag …

Optimizing the thermoelectric performance of zigzag and chiral carbon nanotubes Xiaojian Tan , 1 Huijun Liu , 1 Yanwei Wen , 1 Hongyan Lv , 1 Lu Pan , 1 Jing Shi , 1 and Xinfeng Tang 2 1 Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China

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Periodicity of band gaps of chiral α-graphyne nanotubes

Electronic structures of zigzag (n,0), armchair (n,n), and chiral (n,m) α-graphyne nanotubes (αGNTs) with n = 2-7 were investigated using density functional tight binding calculations. Oscillatory behavior of the band gaps with a period of every (n - m) = 3 was found for each tube. According to the …

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Chirality of single-walled carbon nanotubes | Research ...

2019-10-1 · Chiral vector C can be written as C = n a 1 + m a 2 where a 1 and a 2 are basis vectors of the graphene lattice. The pair of integers (n,m) is called the chiral index or just chirality. This implies that the structure of a single-walled carbon nanotube is completely determined by chirality.

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Chirality of single-walled carbon nanotubes | Research ...

2019-10-1 · Chiral vector C can be written as C = n a 1 + m a 2 where a 1 and a 2 are basis vectors of the graphene lattice. The pair of integers (n,m) is called the chiral index or just chirality. This implies that the structure of a single-walled carbon nanotube is completely determined by chirality.

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Entropy-driven stability of chiral single-walled carbon ...

Above the armchair tubes, chiral (n, n − m) tubes become stable starting with (n, n − 1) and then with increasing (n − m) values such as (6, 5), (7, 5), etc. Chiral tubes—i.e., tubes different from armchair or zigzag tubes—are stabilized at finite temperature by the configurational entropy of the tube edge.

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Entropy-driven stability of chiral single-walled carbon ...

Above the armchair tubes, chiral (n, n − m) tubes become stable starting with (n, n − 1) and then with increasing (n − m) values such as (6, 5), (7, 5), etc. Chiral tubes—i.e., tubes different from armchair or zigzag tubes—are stabilized at finite temperature by the configurational entropy of the tube edge.

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Communication: Origin of the difference between …

2019-3-18 · In this work, we have found that the difference between armchair and zigzag ends of carbon nanotubes (CNTs) does not pertain at close study for individual bonds and thus alternative strategies need to be developed to reach the ultimate goals in selective growth. Based on first-principles simulations, the difference between binding strengths for CNTs of different chirality was investigated ...

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Structure of connections of single-walled carbon …

Abstract. The structures of zigzag-zigzag, armchair-zigzag, zigzag-chiral, armchair-armchair, armchair-chiral, and chiral-chiral pair connections produced by single-walled carbon nanotubes 1.5–5.0 diameter with the use of the combined 5–7 and 4–8 topological defects have been calculated by molecular mechanics methods.

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carbon nanotube | Properties & Uses | Britannica

Under these circumstances, the chiral vectors form a plane perpendicular to the longitude direction of nanotubes and the lengths of the chiral vectors are equal to the circumference. Three different types of SWNTs are distinctly characterized, named “zigzag” (m = 0), “armchair” (n = m), and “chiral.”

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Self-assembled chiral phosphorus nanotubes from ...

Self-assembled chiral phosphorus nanotubes from phosphorene: a molecular dynamics study†. Douxing Pan abc, Tzu-Chiang Wang * b, Chao Wang b, Wei Guo a and Yugui Yao * a a Laboratory of Quantum Functional Material Design and Application, School of Physics, Beijing Institute of Technology, Beijing 100081, China. E-mail: ygyao@bit.edu.cn. b State Key Laboratory of Nonlinear Mechanics, Institute ...

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DFT studies of COOH tip-functionalized zigzag and …

The rim structure of SWCNT in case of zigzag or armchair open ended CNT shows a different pattern. Zigzag carbon nanotubes show metallic or semiconductor properties and their ends shows “saw-tooth” like shape. Functionalized carbon nanotubes are promising candidates in material sciences and nanomedicine [1–3].

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Axial and torsional buckling analysis of single- and …

Armchair, zigzag and chiral types of SWCNTs are made by rolling a monoatomic graphene sheet into a cylinder. MWCNTs are multiple concentric rolled tubes embedded into each other. Due to covalent intermolecular bonding and van der Waals interlayer spacing, there is a geometrical restriction for smallest diameter of the armchair and zigzag types ...

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Electronic and transport properties of nanotubes

This article reviews the electronic and transport properties of carbon nanotubes. The focus is mainly theoretical, but when appropriate the relation with experimental results is mentioned. While simple band-folding arguments will be invoked to rationalize how the metallic or semiconducting character of nanotubes is inferred from their topological structure, more sophisticated tight-binding and ...

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Phonon Dispersion for Armchair and Zigzag Carbon …

Phonon Dispersion for Armchair and Zigzag Carbon Nanotubes. ... So, the primitive lattice translation vectors of CNT are the chiral vector, and the translation vector, which in terms of graphene primitive vectors, are given as: and. Here, , and are integers. The CNT that is obtained by folding the strip OADB will thus consist of two unit cells.

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Phonon Dispersion for Armchair and Zigzag Carbon …

Phonon Dispersion for Armchair and Zigzag Carbon Nanotubes. ... So, the primitive lattice translation vectors of CNT are the chiral vector, and the translation vector, which in terms of graphene primitive vectors, are given as: and. Here, , and are integers. The CNT that is obtained by folding the strip OADB will thus consist of two unit cells.

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Atomsk - Tutorial - Graphene and Nanotubes

If you merge nanotubes of different kinds (zigzag/armchair/chiral), then you may have to duplicate them by different factors along Z so that their lengths match. 4. Nanotubes with different chemical composition. The mode "--create" allows up to two chemical species when constructing nanotubes.