Related papers: Lattice strain at c-Si surfaces: a density functio…
Bragg coherent X-ray diffraction imaging (BCDI) allows the three-dimensional (3D) measurement of lattice strain along the scattering vector for specific microcrystals. If at least three linearly independent reflections are measured, the 3D…
Abridged: Debris disks are valuable systems to study dust properties. Because they are optically thin at all wavelengths, we have direct access to the properties of dust grains. One very promising technique to study them is to measure their…
A density functional for the lattice gas (Ising model) from fundamental measure theory is applied to the problem of droplet states in three-dimensional, finite systems. Similar to previous simulation studies, the sequence of droplets…
An atomistic model based on the Keating potential and the conjugate gradient method are used for simulation of the strain fields for single Ge/Si quantum dots. Calculations are performed in the cluster approximation using clusters…
We derive exact density functionals for systems of hard rods with first-neighbor interactions of arbitrary shape but limited range on a one-dimensional lattice. The size of all rods is the same integer unit of the lattice constant. The…
A recently reported symmetry breaking of density profiles of fluid argon confined by two parallel solid walls of carbon dioxide is studied. The calculations are performed in the framework of a nonlocal density functional theory. It is shown…
The martensitic {\alpha} --> {\omega} transition was investigated in Ti under hydrostatic pressure. The calculations were carried out using the density functional theory (DFT) framework in combination with the Birch-Murnaghan equation of…
A general procedure to investigate the elastic response and calculate the elastic constants of stressed and unstressed materials through continuum field modeling, particularly the phase field crystal (PFC) models, is presented. It is found…
In $e$-beam evaporated amorphous silicon ($a$-Si), the densities of two-level systems (TLS), $n_{0}$ and $\overline{P}$, determined from specific heat $C$ and internal friction $Q^{-1}$ measurements, respectively, have been shown to vary by…
We use the classical version of the density-functional theory in the weighted-density approximation to build up the entire phase diagram and the interface structure of a two-dimensional lattice-gas model which is known, from previous…
The screening of point charges in hydrogenated Si quantum dots ranging in diameter from 10 A to 26 A has been studied using first-principles density-functional methods. We find that the main contribution to the screening function originates…
$0^+$, $1^-$, $2^+$, and $3^-$ excitations of $^{28}\textrm{Si}$ are investigated via proton and $\alpha$ inelastic scattering off $^{28}\textrm{Si}$. The structure calculation of $^{28}\textrm{Si}$ is performed with the energy variation…
The lattice dynamics of coesite has been studied by a combination of diffuse x-ray scattering, inelastic x-ray scattering and an ab initio lattice dynamics calculation. The combined technique gives access to the full lattice dynamics in…
Using the density functional formalism we derive expression for the distortion free energy for systems with continuous broken symmetry and use it to derive expression for the elastic constants of smectic phases in which director is tilted…
The structural and electronic properties of $A$TiO$_3$ ($A$=Ca, Sr, Ba) have been investigated under strain-free situation and with realistic constraints using first-principles calculations. We endeavored to find out the interplay between…
Graphene monolayer grown by Si evaporation from the 0001 surface of SiC displays a moir\'e pattern of corrugation whose structure is ambiguous: different measurements and theoretical studies show either protruding bumps surrounded by…
AxFe2-ySe2 (A=K, Rb, Cs) superconductors may show a complex mixture of structural phases even in a single crystal form. A full sphere of the diffraction intensity has been collected, with the help of synchrotron radiation, for Cs0.8Fe1.6Se2…
A relationship between the chemical composition, structure and luminescent properties of light-emitting SiOxNy(Si) composite layers with Si nanocrystals is demonstrated. Photoluminescence (PL) with a maximum of intensity at 500-600 nm is…
The nanostructure of hydrogenated amorphous silicon (a Si:H) is studied by a combination of small-angle X-ray (SAXS) and neutron scattering (SANS) with a spatial resolution of 0.8 nm. The a-Si:H materials were deposited using a range of…
We present a density-functional theory study addressing the energetics and electronic structure properties of isolated oxygen adatoms at the SrTiO3(001) surface. Together with a surface lattice oxygen atom, the adsorbate is found to form a…