First principles methods and calculations
First principles methods using CASTEP
... Before describing CASTEP in more detail, a brief his- tory of the code follows. It was originally developed by Payne and co-workers in the late 1980’s and early 1990’s [2]. It quickly became a widely used code for ...
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First Principles Lattice Dynamics Calculations of Ag+ Doped KX (X=Cl, Br and I)
... first principles calculations in the past deal with crystals at the zero ...first principles methods can calculate Hellmann-Feynman (H-F) force on atoms with reasonable ...phonon ...
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FIRST PRINCIPLES CALCULATIONS OF CARBON-NANOTUBE AND BORON-NANOTUBE BASED SINGLE ELECTRON TRANSISTORS
... the calculations exhibit the application of DFT to obtain the perceptivities into the different properties of nanotubes based Single-Electron Transistor working in a Coulomb blockade ...approximation ...
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Quantum Monte Carlo calculations of energy gaps from first principles
... (QMC) methods for the calculation of energy gaps from first principles, and present a broad set of excited-state calculations carried out with the variational and fixed-node diffusion QMC ...
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Sound velocities of bridgmanite from density of states determined by nuclear inelastic scattering and first-principles calculations
... space. Methods have ad- vanced substantially in recent years to enable densities and elastic wave velocities of candidate lower mantle as- semblages to be calculated for the appropriate composi- tions at relevant ...
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Strain effects in spinel ferrite thin films from first principles calculations
... states, and only a very small energy gap for NFO. Applying the Hubbard U correction splits the occupied and unoccupied transition metal d-states and shifts them well below and above the Fermi energy (LSDA+U and GGA+U ...
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Exploiting periodic first principles calculations in NMR spectroscopy of disordered solids
... two-dimensional methods have been proposed to overcome this, where fast MAS affords high resolution, but the anisotropic interaction is “recoupled” in a second dimension, producing a sideband manifold that can be ...
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First-Principles Calculations of the Formation and Structures of Point Defects on GaN (0001) Surface
... Table 3 summarizes the lattice parameters and the cohesive energy of α-Ga. Compared with the published values [20] , the error is 2.1%, which implies that our calculation methods are reliable. We calculate the ...
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Unusual structural and electronic properties of porous silicene and germanene: insights from first principles calculations
... Finally, we briefly discuss the possible synthesis approach for c-silicyne. Benefited from the recent devel- opment of metal-assisted coupling methods, several porous nanostructures have been successfully fabri- ...
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Phonon spectrum and thermal properties of cubic Si3N4 from first-principles calculations
... pair-potential methods 40 ( ⬃ 410 GPa) are much larger, as compared with those from experiments ( ⬃ 300 GPA) and DFT ...subsequent calculations, the optimized calculated val- ues of a and x using the LDA ...
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Study on the First-Principles Calculations of Graphite Intercalated by Alkali Metal (Li, Na, K)
... theoretical methods have been used to study insertion properties and mechanisms of Li-GIC, but there are few studies of Na-GICs and systematic differences between Li, Na and ...from first-principles ...
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First-principles calculations of antimony sulphide Sb2S3
... which is cheaper, abundant, and less toxic than any other compound in the group. Therefore, detailed knowledge of electronic and optical properties is essential for understanding its optoelectronic behavior such as band ...
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First-principles calculations on electronic properties of LaNiO3 in solid oxide fuel cell cathodes
... All calculations are performed based on the density functional theory [7] using plane-wave basis sets [8] as implemented in the Quantum Espresso package ...
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Electronic Structures of Ag and Au Adsorbed on TiO2(110) Surfaces by First Principles Calculations
... the calculations were carried out using the program package STATE (Simulation Tool for Atom TEchnology), which has been successfully applied to various systems including TiO 2 (110), 11) Au(111), 12,13) and Au/TiO ...
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Investigating Disorder and Dynamics in Solids: Multinuclear Solid-State NMR and First-Principles Calculations
... • Does the spatial arrangement of the Sn/Ti have any effect on the chemical shift. Is there a shift difference between the different arrangements[r] ...
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First Principles Calculations of Hydrogen Storage on Calcium Decorated, Boron Doped Bilayer Graphene
... Our calculations were carried out using DFT and VASP software packages. In the study, the supercell a 3 × 3 bilayer graphene contains 36 carbon atoms. The interaction potential of ions and electrons is ...
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First principles calculations of properties of orthorhombic iron carbide Fe7C3 at the Earth's core conditions
... margin in the magnetic regime. We note, however, that these values are calculated assuming a ferromagnetic state whereas a paramagnetic regime has been observed experimentally [20]. Thirdly, the enthalpy only describes ...
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The Atomic and Electronic Structure Changes Upon Delithiation of LiCoO2: From First Principles Calculations
... All calculations in the present study are performed at GGA+U level, with the projector augmented wave (PAW) method [19] as implemented in the Vienna ab initio simulation package (VASP) ...
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Vibrational Contribution to the Thermodynamic Properties of Lithium Ion Batteries System: A First Principles Calculations
... sciences, first principles calculation is of most important because of its powerful functionalities in predicting materials structural [5-6], electronic [7, 8], magnetic [9, 10] and other properties ...
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Segregation of hydrogen to defects in nickel using first-principles calculations: The case of self-interstitials and cavities
... the first value is characteristic of trapping to single vacancies, whereas the second one represents clusters involving more vacancies, as initially proposed by the authors of ...
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