相关论文: Polymorphism in $\alpha$-sexithiophene crystals: R…
Controlling the polymorph formation in organic semiconductor thin films by the choice of substrate and deposition temperature is a key factor for targeted device performance. Small molecular semiconductors such as the quadrupolar…
Fermionic path integral Monte Carlo simulations have been applied to study the equilibrium properties of the hydrogen and deuterium in the density and temperature range of 1.6 < rs < 14.0 and 5000K < T < 167000K. We use this technique to…
Methods to efficiently determine the relative stability of polymorphs of organic crystals are highly desired in crystal structure predictions (CSPs). Current methodologies include use of static lattice phonons, quasi-harmonic approximation…
The high critical superconducting temperatures ($T_c$s) of metal hydride phases with clathrate-like hydrogen networks have generated great interest. Herein, we employ the Density Functional Theory-Chemical Pressure (DFT-CP) method to…
A study of high pressure solid Te was carried out at room temperature using Raman spectroscopy and Density Functional Theory (DFT) calculations. The analysis of the P-dependence of the experi- mental phonon spectrum reveals the occurrence…
An adiabatic transition between two equilibrium states corresponding to different stiffnesses in an infinite chain of particles is studied. Initially, the chain particles have random displacements and random velocities corresponding to a…
N-carbophenes are a class of two-dimensional covalent organic frameworks with potential for solid-state gas storage and as 2D topological materials. Previous studies have demonstrated that variations in their bonding, topology, and…
Elastic neutron scattering on a single crystal and powder X-ray diffraction measurements were carried out to investigate how the crystal structure evolves as a function of temperature in the Weyl semimetal WTe$_{2}$. A sharp transition from…
Modern advances in generating ultrabright electron beams have unlocked unprecedented experimental advances based on synchrotron radiation. Current challenges lie in improving the quality of electron sources with novel photocathode materials…
The term "MAX phase" refers to a very interesting and important class of layered ternary transition-metal carbides and nitrides with a novel combination of both metal and ceramic-like properties that have made these materials highly…
Elemental gallium can exist in several phases under ambient conditions. The stable $\alpha$ phase has a superconducting transition temperature, $T_c$, of 0.9~K. By contrast, the $T_c$ of the metastable $\beta$ phase is around 6~K. To…
We have carried out temperature-dependent x-ray diffraction and Raman scattering experiments on powder $Cs_3Bi_2Br_9$. Trigonal to monoclinic structural transition at around 95 K is discussed and shown to be driven by the softening of the…
We have recently predicted and subsequently verified experimentally by specific heat measurements that EuTiO3 undergoes a structural phase transition at elevated temperature TS = 282 K. The origin of the phase transition has been attributed…
Semi-crystalline polymers have been shown to have greatly increased thermal conductivity compared to amorphous bulk polymers due to effective heat conduction along the covalent bonds of the backbone. However, the mechanisms governing the…
The lattice parameters, lattice stability and phonon dispersion curves of five proposed phases of Ti: alpha, beta, gamma, delta and omega are investigated within DFT. It is found that the sequence of high pressure phases at zero temperature…
Though the electrical responses of the various polymorphs found in ferroelectric polycrystalline thin film HfO$_2$ are now well characterized, little is currently understood of this novel material's grain sub-structure. In particular, the…
A stack of titanium foils was irradiated with 136 MeV 136Xe to study microstructure damage and phase stability of titanium upon irradiation. X- ray diffraction, scanning electron microscopy/energy dispersive spectroscopy and atomic force…
Time-domain THz transmission experiment was performed on a $\rm SrBi_2Ta_2O_9$ film deposited on sapphire substrate. Temperatures between 300 and 923 K were investigated and complex permittivity spectra of the film were determined. The…
We investigate theoretically globally nonuniform configurations of quantized-flux vortices in clean superconductors trapped by an external force field that induces a nonuniform vortex density profile. Using an extensive series of numerical…
There exists a variety of theories of the glass transition and many more numerical models. But because the models need built-in complexity to prevent crystallization, comparisons with theory can be difficult. We study the dynamics of a…