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First-principles studies of the local structure and relaxor behavior of Pb ( Mg 1 / 3 Nb 2 / 3 ) O 3 – PbTiO 3 -derived ferroelectric perovskite solid solutions
We have investigated the effect of transition-metal dopants on the local structure of the prototypical 0.75Pb(Mg 1/3 Nb 2/3 )O 3 –0.25PbTiO 3 relaxor ferroelectric. We find that these dopants give rise to very different local structure and other physical properties. For example, when Mg is partially substituted by Cu or Zn, the displacement of Cu or Zn is much larger than that of Mg and is even comparable to that of Nb. The polarization of these systems is also increased, especially for the Cu-doped solution, due to the large polarizability of Cu and Zn. As a result, the predicted maximum dielectric constant temperatures T m are increased. On the other hand, the replacement of a Ti atom with a Mo or Tc atom dramatically decreases the displacements of the cations and the polarization, and thus, the T m values are also substantially decreased. Here, the higher T m cannot be explained by the conventional argument based on the ionic radii of the cations. Furthermore, we find that Cu, Mo, or Tc doping increases the cation displacement disorder. Here, the effect of the dopants on the temperature dispersion ΔT m , which is the change in T m for different frequencies, is also discussed. Our findings lay the foundation for further investigations of unexplored dopants.
Deorbitalized meta-GGA exchange-correlation functionals in solids
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Kinetic modeling of x-ray laser-driven solid Al plasmas via particle-in-cell simulation
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Period proliferation in periodic states in cyclically sheared jammed solids
Athermal disordered systems can display a remarkable response to an applied oscillatory shear: After a relatively few shearing cycles, the system falls into a configuration that had already been visited in a previous cycle. After this point the system repeats its dynamics periodically despite undergoing many particle rearrangements during each cycle. We study here the behavior of orbits as we approach the jamming point in simulations of jammed particles subject to oscillatory shear at fixed pressure and zero temperature. As the pressure is lowered, we find that it becomes more common for the system to find periodic states where it takes multiple cycles before returning to a previously visited state. Thus, there is a proliferation of longer periods as the jamming point is approached.
Linking microscopic and macroscopic response in disordered solids
The modulus of a rigid network of harmonic springs depends on the sum of the energies in each of the bonds due to an applied distortion such as compression in the case of the bulk modulus or shear in the case of the shear modulus. Yet, the distortion need not be global. Here we introduce a local modulus, L i , associated with changing the equilibrium length of a single bond, i , in the network. We show that L i is useful for understanding many aspects of the mechanical response of the entire system. It allows an efficient computation of how the removal of any bond changes the global properties such as the bulk and shear moduli. Additionally, it allows a prediction of the distribution of these changes and clarifies why the changes of these two moduli due to removal of a bond are uncorrelated; these are the essential ingredients necessary for the efficient manipulation of network properties by bond removal.
Molecular mechanics and structure of the fluid-solid interface in simple fluids
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Tuning the magnetocaloric response in half-Heusler/Heusler MnNi 1 + x Sb solid solutions
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Modeling the long-term evolution of dilute solid solutions in the presence of vacancy fluxes
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Particle Lift Challenges and solutions for solid particle receiver systems.
Abstract not provided.
Erratum: An Analysis of Solid-State Electrodeposition-Induced Metal Plastic Flow and Predictions of Stress States in Solid Ionic Conductor Defects [J. Electrochem. Soc., 167, 020534 (2020)]
A corrected equation is provided in this free article.
Rechargeable Solid-State Copper Sulfide Cathodes for Alkaline Batteries: Importance of the Copper Valence State.
Abstract not provided.
Hybrid Solid State ?Chaperone? Phases to Improve Solid State Sodium Electrolytes.
Abstract not provided.