Related papers: Structure of densified germanium dioxide
Germanium dioxide ($GeO_2$) is a chemical analogue of $SiO_2$. Furthermore, it is also to some extent a structural analogue, as the low and high-pressure short-range order (tetrahedral and octahedral) is the same. However, a number of…
In this work we study the high pressure behaviour of liquid and glassy GeO2 by means of molecular dynamics simulations. The interaction potential, which includes dipole polarization effects, was parameterized from first-principles…
Vitreous GeO$_2$ has been compressed at high temperature, to investigate the effect of thermal activation on the structural reorganization during compression. The measurements were performed in-situ using micro Raman spectroscopy under…
High pressure behaviour of liquid GeO2 is investigated by means of molecular dynamics simulations in the pressure range 0-20 GPa and at various temperatures. In agreement with the recent experiments (PRL, 92, 155506, 2004), Ge-O…
Using density functional molecular dynamics simulations we study the electronic properties of glassy g-GeS$_2$. We compute the electronic density of states, which compares very well with XPS measurements, as well as the partial EDOS and the…
Molecular dynamics simulation studies were performed to investigate the structural and dynamic properties of liquid carbon disulfide from ambient to elevated pressure conditions. The results obtained have revealed structural changes at high…
We present a density-functional theory (DFT) study of the structural, electronic, and chemical bonding behaviour in germanium (Ge)-doped vanadium dioxide (VO$_2$). Our motivation is to explain the reported increase of the metal-insulator…
The structural properties of amorphous GeO$_2$, a prototypical network glass, were investigated under ambient to high pressure using reverse Monte Carlo simulations based on reported structure factors from in situ high-pressure neutron…
The structural and electronic properties of germanium clathrates Ge$_{46}$ and K$_8$Ge$_{46}$ are studied by first principles calculations within the local density approximation. The equilibrium structures are obtained by {\em ab initio}…
Understand the nature of liquid structure and its evolution under different conditions is a major challenge in condensed physics and materials science. Here, we report a pressure-induced structure change spanning a wide pressure range in…
The stability of MgH$_2$ has been studied up to 20~GPa using density-functional total-energy calculations. At ambient pressure $\alpha$-MgH${_2}$ takes a TiO$_2$-rutile-type structure. $\alpha$-MgH$_2$ is predicted to transform into…
Large-scale structure of the universe is a useful cosmological probe of the primordial non-Gaussianity and the expansion history of the universe because its topology does not change with time in the linear regime in the standard paradigm of…
Amorphous silica ($a-SiO_2$) is a widely used inorganic material. Interestingly, the relationship between the local atomic structures of $a-SiO_2$ and their effects on ductility and fracture is seldom explored. Here, we combine large-scale…
Simple binary oxide glasses can exhibit a compression behavior distinct from that of their crystalline counterparts. In this study, we employed high-pressure X-ray absorption spectroscopy coupled to the diamond anvil cell to investigate in…
We have studied dense hydrogen and deuterium experimentally up to 320 GPa and using ab initio molecular dynamic (MD) simulations up to 370 GPa between 250 and 300 K. Raman and optical absorption spectra show significant anharmonic and…
In order to control and tailor the properties of nanodots, it is essential to separate the effects of quantum confinement from those due to the surface, and to gain insight into the influence of preparation conditions on the dot physical…
Within the mode-coupling theory for idealized glass transitions, we study the evolution of structural relaxation in binary mixtures of hard spheres with size ratios $\delta$ of the two components varying between 0.5 and 1.0. We find two…
A set of oxide and chalcogenide tetrahedral glasses are investigated using molecular dynamics simulations. It is shown that unlike stoichiometric selenides such as GeSe$_2$ and SiSe$_2$, germania and silica display large standard deviations…
Mg2GeO4 is an analogue for the ultra-high pressure behavior of Mg2SiO4, so we have investigated magnesium germanate to 275 GPa and over 2000 K using a laser-heated diamond anvil cell combined with in situ synchrotron X-ray diffraction and…
We analyse structure and dynamics in simulated high-concentration hard sphere colloidal suspensions by means of calculations based on the void space. We show that remoteness, a quantity measuring the scale of spaces, is useful in studying…