A5086257489- Advanced Chemical Physics Studies
- Rare-earth and actinide compounds
- Magnetic properties of thin films
- Nuclear Materials and Properties
- Machine Learning in Materials Science
- High-pressure geophysics and materials
- Semiconductor materials and interfaces
- Advanced Condensed Matter Physics
- Physics of Superconductivity and Magnetism
- Magnetic Properties of Alloys
- Surface and Thin Film Phenomena
- Catalytic Processes in Materials Science
- Theoretical and Computational Physics
- Magnetic and transport properties of perovskites and related materials
- Magnetic Properties and Applications
- Thermodynamic and Structural Properties of Metals and Alloys
- ZnO doping and properties
- Silicon and Solar Cell Technologies
- Quantum Dots Synthesis And Properties
- Advanced Materials Characterization Techniques
- Quantum and electron transport phenomena
- Astro and Planetary Science
- Electronic and Structural Properties of Oxides
- Nuclear physics research studies
- Semiconductor materials and devices
Ghent University
2015-2024
Ghent University Hospital
2010-2022
VIB-UGent Center for Medical Biotechnology
2017
Material (Belgium)
2016
Ablynx (Belgium)
2014
University of Antwerp
2013
KU Leuven
2001-2012
Universidad Nacional de La Plata
2010
Jülich Aachen Research Alliance
2008-2009
RWTH Aachen University
2008-2009
A comparison of DFT methods Density functional theory (DFT) is now routinely used for simulating material properties. Many software packages are available, which makes it challenging to know the best use a specific calculation. Lejaeghere et al. compared calculated values equation states 71 elemental crystals from 15 different widely codes employing 40 potentials (see Perspective by Skylaris). Although there were variations in values, most recent and converged toward single value, with...
Predictions of observable properties by density-functional theory calculations (DFT) are used increasingly often experimental condensed-matter physicists and materials engineers as data. These predictions to analyze recent measurements, or plan future experiments in a rational way. Increasingly more scientists these fields therefore face the natural question: what is expected error for such first-principles prediction? Information experience about this question implicitly available...
Density-functional theory (DFT) predictions of materials properties are becoming ever more widespread. With increased use comes the demand for estimates accuracy DFT results. In view importance reliable surface properties, this work calculates energies and functions a large diverse test set crystalline solids. They compared to experimental values by performing linear regression, which results in measure predictable material-specific error theoretical result. Two most prevalent functionals,...
We present electronic band structures of transparent oxides calculated using the Tran-Blaha modified Becke-Johnson (TB-mBJ) potential. studied basic n-type conducting binary In(2)O(3), ZnO, CdO and SnO(2) along with p-type ternary delafossite CuXO(2) (X=Al, Ga, In) spinel ZnX(2)O(4) (X=Co, Rh, Ir). The results are presented for gaps effective electron masses. discuss improvements in gap determination TB-mBJ compared to standard generalized gradient approximation (GGA) density functional...
We examine the electronic structure of family ternary zinc spinel oxides ZnX2O4 (X=Al, Ga and In). The band gap ZnAl2O4 calculated using density functional theory (DFT) is 4.25 eV overestimated compared with experimental value 3.8–3.9 eV. DFT ZnGa2O4 2.82 underestimated 4.4–5.0 Since typically underestimates in oxide system, measurements for probably require a correction. use two first-principles techniques capable describing accurately excited states semiconductors, namely GW approximation...
Doping of ceria allows one to tune the mechanical and chemical properties at will, though induced vacancies often contribute leading term these modifications.
We investigate the relation between chain length of ligands used and size nanocrystals formed in hot injection synthesis. With two different CdSe nanocrystal syntheses, we consistently find that longer carboxylic acids result smaller with improved dispersions. By combining a more in-depth experimental investigation kinetic reaction simulations, come to conclusion this tuning is due change diffusion coefficient solubility solute. The by ligand coordination solute further explored expanding...
Abstract By reviewing the experimental and theoretical literature on γ′‐Fe 4 N, by a systematic survey of predictions LDA, PBE, WC, LDA + U (2×), PBE (2×) B3PW91 exchange‐correlation functionals, structural, magnetic hyperfine properties this material as well their pressure dependencies are interpreted. The hypothesis is put forward that N found in Nature exactly at steep transition between low‐spin high‐spin behaviour. ( = 0.4 eV) identified most accurate functional for material, although...
ZnAl${}_{2}$O${}_{4}$ (gahnite) is a ceramic which considered possible transparent conducting oxide (TCO) due to its wide band gap and transparency for UV. Defects play an important role in controlling the conductivity of TCO material along with dopant, main source otherwise insulating oxide. A comprehensive first-principles density functional theory study point defects spinel presented using Heyd, Scuseria, Ernzerhof hybrid (HSE06) overcome problem. We have investigated formation energies...
Fischer–Tropsch synthesis is an attractive process to convert alternative carbon sources, such as biomass, natural gas, or coal, fuels and chemicals. Deactivation of the catalyst obviously undesirable, for a commercial plant it high importance keep active long possible during operating conditions. In this study, reactivity CO on carbon-covered cobalt surfaces has been investigated by means density functional theory (DFT). An attempt made provide insight into role deposition deactivation two...
Using first-principles total energy calculations we have evaluated the thermodynamics and electronic properties of intrinsic vacancy defects in orthorhombic CaZrO3. Charge density atoms-in-molecules concept are used to elucidate changes CaZrO3 upon introduction defects. We explore chemical stability defect formation energies charge-neutral as well charged vacancies under various synthesis conditions also present full partial Schottky reaction energies. The calculated indicate that hole-doped...
The crystal structure of lanthanum cerium oxide (La${}_{2}$Ce${}_{2}$O${}_{7}$) is investigated using ab initio density functional theory calculations. relative stability fluorite- and pyrochlorelike structures studied through comparison their formation energies. These energies show the pyrochlore to be favored over fluorite structure, apparently contradicting conclusions based on experimental neutron x-ray diffraction (XRD). By calculating comparing XRD spectra for a set differently ordered...
Fluorite CeO 2 doped with group IV elements is studied within the density functional theory ( DFT ) and + U framework. Concentration‐dependent formation energies are calculated for Ce 1− x Z O (Z = C, Si , Ge Sn Pb Ti Zr Hf 0 ≤ 0.25 a roughly decreasing trend ionic radius observed. The influence of valence near electronic configuration discussed, indicating importance filled d f shells Fermi level all properties investigated. A clearly different behavior IVa IVb dopants observed: former more...
Experimental nonstoichiometries of colloidal nanocrystals such as CdSe and PbS are accounted for by attributing to each constituent atom capping ligand a formal charge equal its most common oxidation state obtain an overall neutral nanocrystal. In spite apparent simplicity, little theoretical support this approach—called here the oxidation-number sum rule—is present in current literature. Here, we introduce addition energy, which define energy gained or expended upon transfer one from...
The energy-versus-volume curve of the spin-density wave (SDW) in body-centred-cubic Cr is calculated with density functional theory/full-potential linearized augmented plane (DFT/FLAPW) method using generalized gradient approximation (GGA). predicted ground state not SDW, contrast to an earlier FLAPW calculation. A conjecture formulated that widely varying results local (LDA) and GGA - different solution methods can be scaled by size moment. As a consequence, experimentally relevant...
In RIn3 and RSn3 the rare earth (R) is trivalent, except for Eu Yb, which are divalent. This was experimentally determined in 1977 by perturbed angular correlation measurements of electric-field gradient on a 111Cd impurity. At that time, data were interpreted using point charge model, now known to be unphysical unreliable. makes valency determination potentially questionable. We revisit these data, analyze them ab initio calculations gradient. From calculations, physical mechanism...
We determine the temperature dependence of electric-field gradient in hcp-Cd from first principles. The calculations are based on ab initio determination phonon density states spectrum solid. Using only moderate accuracy requirements, is reasonably well reproduced. origin its peculiar ${T}^{3∕2}$ discussed.
We demonstrate how a limited number of ab initio calculations in combination with simple Debye model can predict concentration- and temperature-dependent mixing enthalpy for binary system. Fe-Mo is taken as test case, our predictions are compared phase diagram information recently measured heat solution Mo Fe. Crystallographic magnetic calculated the $\ensuremath{\lambda}$ $\ensuremath{\mu}$ intermetallic phases well. The present methodology be useful making quick survey enthalpies large set...