Journal ArticleDOI
From ultrasoft pseudopotentials to the projector augmented-wave method
Georg Kresse,Daniel P. Joubert +1 more
TLDR
In this paper, the formal relationship between US Vanderbilt-type pseudopotentials and Blochl's projector augmented wave (PAW) method is derived and the Hamilton operator, the forces, and the stress tensor are derived for this modified PAW functional.Abstract:
The formal relationship between ultrasoft (US) Vanderbilt-type pseudopotentials and Bl\"ochl's projector augmented wave (PAW) method is derived. It is shown that the total energy functional for US pseudopotentials can be obtained by linearization of two terms in a slightly modified PAW total energy functional. The Hamilton operator, the forces, and the stress tensor are derived for this modified PAW functional. A simple way to implement the PAW method in existing plane-wave codes supporting US pseudopotentials is pointed out. In addition, critical tests are presented to compare the accuracy and efficiency of the PAW and the US pseudopotential method with relaxed core all electron methods. These tests include small molecules $({\mathrm{H}}_{2}{,\mathrm{}\mathrm{H}}_{2}{\mathrm{O},\mathrm{}\mathrm{Li}}_{2}{,\mathrm{}\mathrm{N}}_{2}{,\mathrm{}\mathrm{F}}_{2}{,\mathrm{}\mathrm{BF}}_{3}{,\mathrm{}\mathrm{SiF}}_{4})$ and several bulk systems (diamond, Si, V, Li, Ca, ${\mathrm{CaF}}_{2},$ Fe, Co, Ni). Particular attention is paid to the bulk properties and magnetic energies of Fe, Co, and Ni.read more
Citations
More filters
Journal ArticleDOI
Continuous-wave lasing in colloidal quantum dot solids enabled by facet-selective epitaxy
Fengjia Fan,Oleksandr Voznyy,Randy P. Sabatini,Kristopher T. Bicanic,Michael M. Adachi,Michael M. Adachi,James R. McBride,Kemar R. Reid,Young-Shin Park,Young-Shin Park,Xiyan Li,Ankit Jain,Rafael Quintero-Bermudez,Mayuran Saravanapavanantham,Min Liu,Marek Korkusinski,Pawel Hawrylak,Victor I. Klimov,Sandra J. Rosenthal,Sjoerd Hoogland,Edward H. Sargent +20 more
TL;DR: A way to decrease the band-edge degeneracy and single-dot photoluminescence linewidth in CQDs by means of uniform biaxial strain is demonstrated and continuous-wave lasing from CQD solids is demonstrated, expanding the library of solution-processed materials that may be capable of continuous- wave lasing.
Journal ArticleDOI
Effects of cation d states on the structural and electronic properties of III-nitride and II-oxide wide-band-gap semiconductors
TL;DR: In this paper, the structural and electronic properties of wurtzite MgO, ZnO, and CdO were investigated using first-principles methods based on density functional theory within the local density approximation (LDA).
Journal ArticleDOI
First principles high throughput screening of oxynitrides for water-splitting photocatalysts
TL;DR: In this paper, a high throughput screening system was presented to search for new water-splitting photocatalysts, including three binary nitrides, two ternary oxynitrides and eleven quaternary Oxynitrinides.
Journal ArticleDOI
Composition and temperature of the Earth's core constrained by combining ab initio calculations and seismic data
TL;DR: In this article, it is shown how ab initio techniques based on density functional theory can be used to calculate the chemical potentials of the leading candidate impurity elements (S, O and Si) in the Earth's solid inner core and liquid outer core.
Journal ArticleDOI
Indirect to direct bandgap transition in methylammonium lead halide perovskite
Tianyi Wang,Benjamin Daiber,Jarvist M. Frost,Sander A. Mann,Erik C. Garnett,Aron Walsh,Bruno Ehrler +6 more
Abstract: Methylammonium lead iodide perovskites are considered direct bandgap semiconductors. Here we show that in fact they present a weakly indirect bandgap 60 meV below the direct bandgap transition. This is a consequence of spin–orbit coupling resulting in Rashba-splitting of the conduction band. The indirect nature of the bandgap explains the apparent contradiction of strong absorption and long charge carrier lifetime. Under hydrostatic pressure from ambient to 325 MPa, Rashba splitting is reduced due to a pressure induced reduction in local electric field around the Pb atom. The nature of the bandgap becomes increasingly more direct, resulting in five times faster charge carrier recombination, and a doubling of the radiative efficiency. At hydrostatic pressures above 325 MPa, MAPI undergoes a reversible phase transition resulting in a purely direct bandgap semiconductor. The pressure-induced changes suggest epitaxial and synthetic routes to higher efficiency optoelectronic devices.
References
More filters
Book
Planewaves, Pseudopotentials, and the LAPW Method
TL;DR: The linearized augmented planewave (LAPW) method has emerged as the standard by which density functional calculations for transition metal and rare-earth containing materials are judged.
Related Papers (5)
Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set.
Georg Kresse,Jürgen Furthmüller +1 more