The SIESTA method for ab initio order-N materials simulation
José M. Soler,Emilio Artacho,Julian D. Gale,Alberto García,Javier Junquera,Javier Junquera,Pablo Ordejón,Daniel Sánchez-Portal +7 more
TLDR
In this paper, a selfconsistent density functional method using standard norm-conserving pseudopotentials and a flexible, numerical linear combination of atomic orbitals basis set, which includes multiple-zeta and polarization orbitals, was developed and implemented.Abstract:
We have developed and implemented a selfconsistent density functional method using standard norm-conserving pseudopotentials and a flexible, numerical linear combination of atomic orbitals basis set, which includes multiple-zeta and polarization orbitals. Exchange and correlation are treated with the local spin density or generalized gradient approximations. The basis functions and the electron density are projected on a real-space grid, in order to calculate the Hartree and exchange-correlation potentials and matrix elements, with a number of operations that scales linearly with the size of the system. We use a modified energy functional, whose minimization produces orthogonal wavefunctions and the same energy and density as the Kohn-Sham energy functional, without the need for an explicit orthogonalization. Additionally, using localized Wannier-like electron wavefunctions allows the computation time and memory required to minimize the energy to also scale linearly with the size of the system. Forces and stresses are also calculated efficiently and accurately, thus allowing structural relaxation and molecular dynamics simulations.read more
Citations
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A type-II GeSe/SnS heterobilayer with a suitable direct gap, superior optical absorption and broad spectrum for photovoltaic applications
TL;DR: In this article, the authors predicted that the GeSe/SnS heterobilayer has a direct band structure with a gap value of about 1.519 eV and typical type-II band alignment.
Journal ArticleDOI
Charge separation via strain in silicon nanowires.
TL;DR: The possibility of utilizing partial strain for charge separation at the nanoscale opens up a new avenue for designing solar cells by morphology control, where effectively a type-II homojunction is formed and charge separation is facilitated by thermalization.
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Quantum confinement and dielectric profiles of colloidal nanoplatelets of halide inorganic and hybrid organic–inorganic perovskites
TL;DR: By inspecting 2D HOP, it is found that it cannot be described as a simple superposition of independent inorganic and organic layers, and the dramatic impact of ionic contributions on the dielectric constant εs is analysed.
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Effect of Compensated Codoping on the Photoelectrochemical Properties of Anatase TiO2 Photocatalyst
TL;DR: In this paper, an effective codoping approach is described to modify the photoelectrochemical properties of anatase TiO2 by doping with nonmetal (N or C) and transition metal (Nb or Ta) impurities.
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Electronic Structure of TiO2 Surfaces and Effect of Molecular Adsorbates Using Different DFT Implementations
TL;DR: In this article, the effect of adsorption of benzoic acid on the electronic structure of the TiO2−adsorbate system was investigated using density functional theory (DFT) and the accuracy and efficiency of several DFT implementations (plane waves vs localized basis sets, all-electron vs pseudopotential calculations) were evaluated.
References
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Generalized Gradient Approximation Made Simple
TL;DR: A simple derivation of a simple GGA is presented, in which all parameters (other than those in LSD) are fundamental constants, and only general features of the detailed construction underlying the Perdew-Wang 1991 (PW91) GGA are invoked.
Journal ArticleDOI
Special points for brillouin-zone integrations
Hendrik J. Monkhorst,J.D. Pack +1 more
TL;DR: In this article, a method for generating sets of special points in the Brillouin zone which provides an efficient means of integrating periodic functions of the wave vector is given, where the integration can be over the entire zone or over specified portions thereof.
Journal ArticleDOI
Self-Consistent Equations Including Exchange and Correlation Effects
Walter Kohn,L. J. Sham +1 more
TL;DR: In this paper, the Hartree and Hartree-Fock equations are applied to a uniform electron gas, where the exchange and correlation portions of the chemical potential of the gas are used as additional effective potentials.
Book
Introduction to solid state physics
TL;DR: In this paper, the Hartree-Fock Approximation of many-body techniques and the Electron Gas Polarons and Electron-phonon Interaction are discussed.