1.5k citations · 2.9k across the 24 of their papers we have counts for
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Enhancement of hydrogen absorption and hypervalent metal hydride formation in lanthanum using cryogenic ball milling
Sakun Duwal, Vitalie Stavila, Catalin Spataru +11
Rare earth superhydrides exhibit high temperature superconductivity but are difficult to characterize and use in applications due to their high formation and stability pressures, w…
Quantitative kinetic rules for plastic strain-induced - phase transformation in Zr under high pressure
Achyut Dhar, Valery I. Levitas, K. K. Pandey +3
Plastic strain-induced phase transformations (PTs) and chemical reactions under high pressure are broadly spread in modern technologies, friction and wear, geophysics, and astrogeo…
Effect of particle size on the phase transformation behavior and equation of state of Si under hydrostatic loading
Sorb Yesudhas, Valery I. Levitas, Feng Lin +2
High-pressure synchrotron X-ray diffraction (XRD) studies have been conducted on three types of Si particles (micron, 100 nm, and 30 nm). The pressure for initiation of Si-I->Si-II…
Observation of a new polyhalide phase in Ag-Cl system at high pressure
Adam Grzelak, Jakub Gawraczynnski, Mariana Derzsi +3
In this short contribution, we examine Raman spectroscopic data from high-pressure and high-temperature experiments with Ag-Cl system, and find that they are in good agreement…
Helium-hydrogen immiscibility at high pressures
Yu Wang, Xiao Zhang, Shuqing Jiang +6
Hydrogen and helium are the most abundant elements in the universe and they constitute the interiors of gas giant planets. Thus, their equations of states, phase, chemical state, a…
Evidence for superconductivity above 260 K in lanthanum superhydride at megabar pressures
Maddury Somayazulu, Muhtar Ahart, Ajay K Mishra +5
Recent predictions and experimental observations of high Tc superconductivity in hydrogen-rich materials at very high pressures are driving the search for superconductivity in the…
Superconductivity in SrB3C3 clathrate
Li Zhu, Hanyu Liu, Maddury Somayazulu +12
We predict superconductivity for the carbon-boron clathrate SrB3C3 at 27-43 K for Coulomb pseudopotential (mu*) values between 0.17 and 0.10 using first-principles calculations wit…
Synthesis of Polar Ordered Oxynitride Perovskite
Muhtar Ahart, Maddury Somayazulu, Rajasekarakumar Vadapoo +5
For decades, numerous attempts have been made to produce polar oxynitride perovskites, where some of the oxygen are replaced by nitrogen, but a polar ordered oxynitride has never b…
Backbone NxH Compounds at High Pressures
Alexander F. Goncharov, Nicholas Holtgrewe, Guangrui Qian +11
Optical and synchrotron x-ray diffraction diamond anvil cell experiments have been combined with first principles theoretical structure predictions to investigate mixed N2 and H2 u…
Unexpected stable stoichiometries of sodium chlorides
Weiwei Zhang, Artem R. Oganov, Alexander F. Goncharov +7
Sodium chloride (NaCl), or rocksalt, is well characterized at ambient pressure. Due to the large electronegativity difference between Na and Cl atoms, it has highly ionic chemical…
Unexpected stable stoichiometries of sodium chlorides
Weiwei Zhang, Artem R. Oganov, Alexander F. Goncharov +5
At ambient pressure, sodium, chlorine, and their only known compound NaCl, have well-understood crystal structures and chemical bonding. Sodium is a nearly-free-electron metal with…
Pressure-induced alpha-to-omega transition in titanium metal: A systematic study of the effects of uniaxial stress
Daniel Errandonea, Y. Meng, M. Somayazulu +1
We investigated the effects of uniaxial stress on the pressure-induced alpha-to-omega transition in pure titanium (Ti) by means of angle dispersive x-ray diffraction in a diamond-a…
Melting of tantalum at high pressure determined by angle dispersive x-ray diffraction in a double-sided laser-heated diamond-anvil cell
D. Errandonea, M. Somayazulu, D. Hausermann +1
The high pressure and high temperature phase diagram of Ta has been studied in a laser-heated diamond-anvil cell (DAC) using x-ray diffraction measurements up to 52 GPa and 3800 K.…
Effects of pressure on the local atomic structure of CaWO4 and YLiF4: Mechanism of the scheelite-to-wolframite and scheelite-to-fergusonite transitions
D. Errandonea, F. J. Manjon, M. Somayazulu +1
The pressure response of the scheelite phase of CaWO4 (YLiF4) and the occurrence of the pressure induced scheelite-to-wolframite (M-fergusonite) transition are reviewed and discuss…
New Phases of Solid Nitrogen
Eugene Gregoryanz, Alexander Goncharov, Russell J. Hemley +3
We report the discovery of a new class of molecular phases of solid nitrogen at high pressures and temperatures by Raman and infrared spectroscopy and powder x-ray diffraction. Unl…