Related papers: Molecular and polymeric amorphous forms in dense S…
We report the results of the X-ray diffraction study of B2O3 glass in the pressure interval up to 10 GPa in the 300-700 K temperature range, the results of in-situ volumetric measurements of the glass at pressures up to 9 GPa at room…
Polymorphism is ubiquitous in crystalline solids. Amorphous solids, such as glassy water and silicon, may undergo amorphous-to-amorphous transitions (AATs). The nature of AATs remains ambiguous, due to diverse system-dependent behaviors and…
Fluorite oxides such as HfO$_2$ exhibit rich and tunable phase behavior, making them promising candidates for next generation electronic devices. A key challenge is to design amorphous HfO$_2$-based high-$k$ materials with both structural…
Nitrogen represents an archetypal example of material exhibiting a pressure driven transformation from molecular to polymeric state. Detailed investigations of such transformations are challenging because of a large kinetic barrier between…
Polytypism of incommensurately modulated structures was hitherto unobserved. Here, we found the phenomenon in simple halogen systems of bromine and iodine upon molecular dissociation in the solids under pressure. Single-crystal synchrotron…
The behavior of a confined spherical symmetric anomalous fluid under high external pressure was studied with Molecular Dynamics simulations. The fluid is modeled by a ore-softened potential with two characteristic length scales, which in…
It has been hypothesized that liquid polyamorphism, the existence of multiple amorphous states in a single component substance, may be caused by molecular or supramolecular interconversion. A simple microscopic model [Caupin and Anisimov,…
Recent advances of highly efficient solar cells based on organic-inorganic halide perovskites have triggered intense research efforts to establish the fundamental properties of these materials. In this work, we utilized diamond anvil cell…
We investigate the behavior of amorphous silicon under hydrostatic compression using molecular simulations. During compression, amorphous silicon undergoes a discontinuous nonequilibrium transition from a low-density to a high-density…
Under pressure, metals exhibit increasingly shorter interatomic distances. Intuitively, this response is expected to be accompanied by an increase in the widths of the valence and conduction bands and hence a more pronounced…
We develop a theory of anomalous elasticity in disordered two-dimensional flexible materials with orthorhombic crystal symmetry. Similar to the clean case, we predict existence of infinitely many flat phases with anisotropic bending…
We report molecular dynamics simulations of a hydrophobic polymer-chain in aqueous solution between $260 {K}$ and $420 {K}$ at pressures of $1 {bar}$, $3000 {bar}$, and $4500 {bar}$. The simulations reveal a hydrophobically collapsed state…
An order parameter with broken polarization symmetry is proposed for the pressure-induced molecular dissociation transitions in nitrogen. The experimental dissociative transition pressure dependence of the calculated order parameter is well…
We use molecular dynamics simulations in two dimensions to investigate the possibility that a core-softened potential can reproduce static and dynamic anomalies found experimentally in liquid water: (i) the increase in specific volume upon…
Available simulation methods, suitable to describe solid-solid phase transitions occurring upon increasing of presssure and/or temperature, are based on empirical interatomic potentials: this restriction reduces the predictive power, and…
Structural changes of Li2C2 under pressure were studied by synchrotron x-ray diffraction in a diamond anvil cell under hydrostatic conditions and by using evolutionary search methodology for crystal structure prediction. We show that the…
There is an increasing interest in the amorphous states of metal-organic frameworks (MOFs) and porous coordination polymers, which can be produced by pressure-induced amorphization, temperature-induced amorphization, melt-quenching,…
The behaviour of alkaline carbonates at high pressure is poorly understood. Indeed, theoretical and experimental investigations of general trends of pressure induced structural changes appear in the literature only sporadically. In this…
The anomalous $\lambda$-transition of liquid sulfur, which is supposed to be related to the transformation of eight-membered sulfur rings into long polymeric chains, has attracted considerable attention. However, a detailed description of…
We study numerically an atomistic model which is shown to exhibit a one--step crystal--to--amorphous transition upon decompression. The amorphous phase cannot be distinguished from the one obtained by quenching from the melt. For a…