Projector Augmented Wave Method with Gauss-Type Atomic Orbital Basis: Implementation of the Generalized Gradient Approximation and Mesh Grid Quadrature

Ab-intio investigations of atomic and molecular oxygen on TiNi(110) surface are performed by using the projector augmented wave method with generalized gradient approximation for the exchange-correlation functional. Our results confirm the formation of a Ni-rich interface TiO2(100)/TiNi(110), for which the formation energies (Hf) of point defects at the interfacial layers were estimated. It is shown that Hf of swap Ti-Ni defect has a lower energy than that for the Ni antisites at the interfacial layers. The formation energies of point defects in bulk TiNi, monoclinic TiO, and rutile TiO2 are also calculated. Our results demonstrate that Hf of Ni-antisites in TiO is twice less than that in TiO2. The formation of small Ni clusters is also discussed.

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Structural and Electronic Properties of ScC and NbC: A First Principles Study

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.194.276 ◽

2012 ◽

Vol 194 ◽

pp. 276-279 ◽

Cited By ~ 2

Author(s):

Gladys Patricia Abdel Rahim ◽

Jairo Arbey Rodríguez

Keyword(s):

Electronic Properties ◽

First Principles ◽

Niobium Carbide ◽

Full Potential ◽

Wave Method ◽

Generalized Gradient ◽

Plane Wave Method ◽

Generalized Gradient Approximation ◽

Structural And Electronic Properties ◽

Correlation Potential

We study the structural and electronic properties of scandium carbide ScC and niobium carbide NbC in both the sodium chloride rock salt (NaCl) and wurtzite structures by means of accurate first principles total energy calculations. The calculations were performed employing the full-potential linearized plane wave method (FP-LAPW). We used the generalized gradient approximation (GGA) of Perdew Burke and Ernzerhof for the exchange and correlation potential. Volume optimization and density of states including spin (DOS) of the systems are presented.

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Stress Formulation in the All-Electron Full-Potential Linearized Augmented Plane Wave Method: II. Accuracy Check in the Generalized Gradient Approximation

Journal of the Physical Society of Japan ◽

10.7566/jpsj.82.044701 ◽

2013 ◽

Vol 82 (4) ◽

pp. 044701

Author(s):

Naoyuki Nagasako ◽

Tamio Oguchi

Keyword(s):

Plane Wave ◽

Full Potential ◽

Wave Method ◽

Generalized Gradient ◽

Augmented Plane Wave ◽

Plane Wave Method ◽

Generalized Gradient Approximation ◽

Augmented Plane Wave Method ◽

Accuracy Check ◽

Linearized Augmented Plane Wave

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Structural and Electronic Properties of Armchair GaN Nanoribbons with AlN Edges: First-Principles Study

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.771.101 ◽

2013 ◽

Vol 771 ◽

pp. 101-104

Author(s):

Xiu Juan Du ◽

Zheng Chen ◽

Jing Zhang ◽

Zhao Rong Ning

Keyword(s):

Electronic Properties ◽

First Principles ◽

Function Theory ◽

Density Function Theory ◽

Band Gaps ◽

Ribbon Width ◽

Generalized Gradient ◽

Generalized Gradient Approximation ◽

Structural And Electronic Properties ◽

Projector Augmented Wave

Under the generalized gradient approximation (GGA), the structural and electronic properties of armchair GaN nanoribbons with AlN edges have been investigated by using the first-principles projector-augmented wave (PAW) potential within the density function theory (DFT) framework. The results reflect that the band gaps of the armchair GaN nanoribbons (AGaNNRs) are vibrated with the increasing ribbon width. For Al, Ga, H and N atom, the successively increasing electronegativity of 3.04, 2.1, 1.81 and 1.61 causes the successive increase of the charge density. These results are very useful for the applications of the AGaNNRs.

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Surface energies and relaxation of NiCoCr and NiFeX (X=Cu, Co or Cr) equiatomic multiprincipal element alloys from first principles calculations

Modelling and Simulation in Materials Science and Engineering ◽

10.1088/1361-651x/ac3e07 ◽

2021 ◽

Author(s):

Wei Li ◽

Xianghe Peng ◽

Alfonso H W Ngan ◽

Jaafar El-Awady

Keyword(s):

First Principles ◽

First Principles Calculations ◽

Generalized Gradient ◽

Principal Element ◽

Fracture Properties ◽

Catalytic Activities ◽

Surface Energies ◽

Generalized Gradient Approximation ◽

Projector Augmented Wave ◽

Cutting Model

Abstract First principles calculations of the energies and relaxation of unreconstructed low-index surfaces, i.e. (001), (011) and (111) surfaces, in NiCoCr and NiFeX (X=Cu, Co or Cr) equiatomic multi-principal element alloys are presented. The calculations were conducted for twelve-layer slabs represented by special quasi-random supercells using the projector augmented wave method within the generalized gradient approximation. While experimental predictions are unavailable for comparison, the calculated surface energies agree fairly well with those from thermodynamic modeling and a bond-cutting model. In addition, the calculations unveil an important surface structure, namely, that the topmost surface layer is in contraction except for the (001) surface of NiFeCr alloy, the next layer below is in extension, and the bulk spacing is gradually recovered from the subsequent layers down. Additionally, the surface contraction is the most pronounced on the (011) plane, being about 4-10% relative to the bulk spacings. The results presented here can provide an understanding of surface-controlled phenomena such as corrosion, catalytic activities and fracture properties in these equiatomic multi-principal element alloys.

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Interstitial vs. Substitutional Metal Insertion in V2O5 as Post-Lithium Ion Battery Cathode: A Comparative GGA/GGA+U Study with Localized Bases

10.26434/chemrxiv.12029709.v1 ◽

2020 ◽

Author(s):

Daniel Koch ◽

Sergei Manzhos

Keyword(s):

Electronic Structure ◽

Plane Wave ◽

Transition Metal Oxides ◽

Reasonable Agreement ◽

Correction Term ◽

Lithium Ion ◽

Generalized Gradient ◽

Main Group Metals ◽

Generalized Gradient Approximation ◽

Metal Insertion

The generalized gradient approximation (GGA) often fails to correctly describe the electronic structure and thermochemistry of transition metal oxides and is commonly improved using an inexpensive correction term with a scaling parameter U. We tune U to reproduce experimental vanadium oxide redox energetics with a localized basis and a GGA functional. We find the value for U to be significantly lower than what is generally reported with plane-wave bases, with the uncorrected GGA results being in reasonable agreement with experiments. We use this computational setup to calculate interstitial and substitutional <a>insertion energies of main group metals in vanadium pentoxide</a> and find <a>interstitial doping to be thermodynamically favored</a>.

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