Related papers: Amorphous ZrO2 from Ab-initio molecular dynamics: …
Understanding the response of ceramics operating in extreme environments is of interest for a variety of applications. Ab initio molecular dynamic simulations have been used to investigate the effect of structure and $B$-site (=Ti, Zr)…
The intermetallic compound Zr3Al is severely deformed by the method of repeated cold rolling. By X-ray diffraction it is shown that this leads to amorphization. TEM investigations reveal that a homogeneously distributed debris of very small…
The static and dynamic structure of liquid Al is studied using the orbital free ab-initio molecular dynamics method. Two thermodynamic states along the coexistence line are considered, namely T = 943 K and 1323 K for which X-ray and neutron…
Amorphous solids exhibit intrinsic, local structural transitions, that give rise to the well known quantum-mechanical two-level systems at low temperatures. We explain the microscopic origin of the electric dipole moment of these two-level…
The mechanical loss angle of amorphous TiO$_2$-doped GeO$_2$ can be lower than 10$^{-4}$, making it a candidate for Laser Interferometer Gravitational-wave Observatory (LIGO) mirror coatings. Amorphous oxides have complex atomic structures…
We report here a study of reversible pressure-induced structural transformation between two amorphous forms of SO$_2$: molecular at pressures below 26 GPa and polymeric above this pressure, at temperatures of 77 - 300 K. The transformation…
Crystalline $\rm Bi_2Se_3$ is one of the most explored three-dimensional topological insulator, with a $0.3\;\rm eV$ energy gap making it promising for applications. Its amorphous counterpart could bring to light new possibilities for large…
The large, temperature-independent, low-frequency dielectric constant recently observed in single-crystal CaCu{3}Ti{4}O{12} is most plausibly interpreted as arising from spatial inhomogenities of its local dielectric response. Probable…
With the use of {\em ab initio} based molecular dynamics simulations we study the structural, dynamical and electronic properties of glassy g-GeS$_2$ at room temperature. From the radial distribution function we find nearest neighbor…
Amorphous solids display numerous universal features in their mechanics, structure, and response. Current models assume heterogeneity in mesoscale elastic properties, but require fine-tuning in order to quantitatively explain vibrational…
The structural relaxation of amorphous materials is described as arising from the superposition of elementary processes with varying activation energies. We show that it is possible to obtain the kinetic parameters of these processes from…
The structure-property relation of nanostructured Al-doped ZnO thin films has been investigated in detail through a systematic variation of structure and morphology, with particular emphasis on how they affect optical and electrical…
The structural and electronic properties of amorphous silicon ($a$-Si) are investigated by first-principles calculations based on the density-functional theory (DFT), focusing on the intrinsic structural defects. By simulated melting and…
We report results of ab initio constant-pressure molecular dynamics simulations of sulfur compression leading to structural transition and pressure-induced amorphization. Starting from the orthorhombic S-I phase composed of S$_8$ ring…
The ferroelectric trends of rutile (TiO$_2$) in bulk and at the (110) surface are investigated by means of ab initio density functional theory. We discuss the underlying mechanism of the incipient ferroelectric behavior of rutile in terms…
It is suggested that the dynamics of liquid water has a component consisting of O^{-2z} (oxygen) anions and H^{+z} (hydrogen) cations, where z is a (small) reduced effective electron charge. Such a model may apply to other similar liquids.…
We report a phonon density of states measurement of $\alpha$-ZnCl$_{2}$ using the coherent inelastic neutron scattering technique and a lattice dynamical calculation in four crystalline phases of ZnCl$_{2}$ using a transferable interatomic…
The dielectric response and structural properties of finite-temperature electron liquids are central to accurately describing the physical behavior of electronic systems. This study presents a robust analytical model for the static…
The discovery of very large piezo- and pyroelectric effects in ZrO2 and HfO2-based thin films opens up new opportunities to develop silicon-compatible sensor and actor devices. The effects are amplified close to the polar-orthorhombic to…
In order to model experimental non-resonant Raman optical activity, chemists must compute a host of second-order response tensors, (e.g. the electric-dipole magnetic-dipole polarizability) and their nuclear derivatives along a set of…