Related papers: Evidence for a new extended solid of nitrogen
The phase diagram of oxygen is investigated for pressures from 50 to 130~GPa and temperatures up 1200 K using first principles theory. A metallic molecular structure with the $P6_3/mmc$ symmetry ($\eta^{'}$ phase) is determined to be…
Niobium polyhydride was synthesized at high pressure and high temperature conditions by using diamond anvil cell combined with in situ high pressure laser heating techniques. High pressure electric transport experiments demonstrate that…
A new phase V of hydrogen was recently claimed in experiments above 325 GPa and 300 K. Due to the extremely small sample size at such record pressures the measurements were limited to Raman spectroscopy. The experimental data on increase of…
Numerical computations employing detailed chemistry are used to characterize the different combustion modes emerging in mixing layers separating nitrogen-diluted counterflowing planar streams of hydrogen and oxygen. Attention is focused on…
Lithium nitrate LiNO$_3$ is identified to possess a dielectric constant $\epsilon$' larger than 6x10$^6$ at 1 kHz in powder samples above the critical temperature $T$$_W$ = 306 K. For single crystalline samples, $\epsilon$' can be sustained…
Crystalline microporous materials are solids formed by interconnected pores of less than 2 nm in size. Typically, they possess large surface areas desirable for versatile applications such as catalysis, gas adsorption, and energy storage.…
While preserving many of the unusual features of single-layer graphene, few-layer graphene (FLG) provides a richness and flexibility of electronic structure that render this set of materials of great interest for both fundamental studies…
La$_3$Ni$_2$O$_7$ exists in two polymorphs: an unconventional structure with alternating layers of single- and triple-layered nickel-oxygen octahedra, and a classical double-layered Ruddlesden-Popper phase. In this study, we report the…
A new dislocation structure-square-octagon pair (4|8) is discovered in two-dimensional boron nitride (h-BN), via first-principles calculations. It has lower energy than corresponding pentagon-heptagon pairs (5|7), which contain unfavorable…
We report the discovery of a new molecular phase of carbon dioxide at high-pressure and high-temperature. Using x-ray diffraction, we identify this phase as the theoretically predicted high-temperature Cmca phase [Bonev et al., Phys. Rev.…
We reported on the observation of extremely high-density ($>10^{14}$cm$^{-2}$) 2D electron gas in N-polar AlGaN/GaN heterostructures grown on sapphire substrates. Due to introducing the GaN/AlN superlattice (SL) back barrier between the GaN…
In the nitrogen-doped lutetium hydride (Lu-H-N) system, the presence of Lu-N chemical bonds plays a key role in the emergence of possible room-temperature superconductivity at near ambient pressure. However, due to the synthesis of…
A discharge of nitrogen gas, as created in a microwave-induced plasma, exhibits a very dense molecular emission line spectrum. Emission spectra of this kind could serve as wavelength calibrators for high-resolution astrophysical…
Suspended Bernal-stacked graphene multilayers up to an unexpectedly large thickness exhibit a broken-symmetry ground state, whose origin remains to be understood. Here we show that a finite-temperature second order phase transition occurs…
We have performed a combined experimental and theoretical study of ethane and methane at high pressures up to 120 GPa at 300 K using x-ray diffraction and Raman spectroscopy and the USPEX ab-initio evolutionary structural search algorithm,…
Experimental progress finally reached the metallic solid hydrogen phase, which was predicted by Wigner and Huntington over 80 years ago. However, the different structures in the phase diagram are still been debated due to the difficulty of…
Optical properties of compressed fluid hydrogen in the region where dissociation and metallization is observed are computed by ab-initio methods and compared to recent experimental results. We confirm that above 3000 K both processes are…
Data of 23Na NMR spectra- and relaxation measurements are interpreted as suggesting that, upon increasing temperature the Na layers in Na0.8CoO2 adopt a 2D liquid state at T=291 K. The corresponding first order phase transition is preceded…
We have discovered a new compound of the composition ScPd2Al3 crystallizing in unknown structure type. Moreover, ScPd2Al3 reveals polymorphism. We have found an orthorhombic crystal structure at room temperature and a high temperature cubic…
We investigate the pressure-driven structural and electronic evolution of PdSe\(_2\) using powder X-ray diffraction, Raman spectroscopy, and first-principles calculations. Beyond 2.3 GPa, suppression of the Jahn-Teller distortion induces…