Comparing first-principles density functionals plus corrections for the lattice dynamics of YBa2Cu3O6.

The enigmatic mechanism underlying unconventional high-temperature superconductivity, especially the role of lattice dynamics, has remained a subject of debate. Theoretical insights have long been hindered due to the lack of an accurate first-principles description of the lattice dynamics of cuprates. Recently, using the r2SCAN meta-generalized gradient approximation (meta-GGA) functional, we have been able to achieve accurate phonon spectra of an insulating cuprate YBa2Cu3O6 and discover significant magnetoelastic coupling in experimentally interesting Cu-O bond stretching optical modes [Ning et al.

Assessing r2SCAN meta-GGA functional for structural parameters, cohesive energy, mechanical modulus, and thermophysical properties of 3d, 4d, and 5d transition metals.

The recent development of accurate and efficient semilocal density functionals on the third rung of Jacob's ladder of density functional theory, such as the revised regularized strongly constrained and appropriately normed (r2SCAN) density functional, could enable rapid and highly reliable prediction of the elasticity and temperature dependence of thermophysical parameters of refractory elements and their intermetallic compounds using the quasi-harmonic approximation (QHA). Here, we present a comparative evaluation of equilibrium cell volumes, cohesive energy, mechanical moduli, and thermophysical properties (Debye temperature and thermal expansion coefficient) for 22 transition metals using semilocal density functionals, including the local density approximation (LDA), Perdew-Burke-Ernzerhof (PBE) and PBEsol generalized gradient approximations (GGAs), and the r2SCAN meta-GGA. PBEsol and r2SCAN deliver the same level of accuracies for structural, mechanical, and thermophysical properties.

Layered Semiconductor CrGaTe with Concurrent Broken Inversion Symmetry and Ferromagnetism: A Bulk Ferrovalley Material Candidate.

The valleytronic state found in group-VI transition-metal dichalcogenides such as MoS has attracted immense interest since its valley degree of freedom could be used as an information carrier. However, valleytronic applications require spontaneous valley polarization. Such an electronic state is predicted to be accessible in a new ferroic family of materials, i.

Testing the rSCAN Density Functional for the Thermodynamic Stability of Solids with and without a van der Waals Correction.

A central aim of materials discovery is an accurate and numerically reliable description of thermodynamic properties, such as the enthalpies of formation and decomposition. The rSCAN revision of the strongly constrained and appropriately normed (SCAN) meta-generalized gradient approximation (meta-GGA) balances numerical stability with high general accuracy. To assess the rSCAN description of solid-state thermodynamics, we evaluate the formation and decomposition enthalpies, equilibrium volumes, and fundamental band gaps of more than 1000 solids using rSCAN, SCAN, and PBE, as well as two dispersion-corrected variants, SCAN+rVV10 and rSCAN+rVV10.

Egyptian blue: from pigment to battery electrodes.

Herein we report on using Egyptian blue as an anode material for Li-ion batteries. A 1 cycle lithiation capacity of 594 mA h g and reversible capacity of 210 mA h g at 20 mA g, and at 500 mA g a reversible capacity of 120 mA h g (stable over 1000 cycles) were achieved with coulombic efficiency more than 99.5%.

Construction of meta-GGA functionals through restoration of exact constraint adherence to regularized SCAN functionals.

The strongly constrained and appropriately normed (SCAN) meta-GGA exchange-correlation functional [Sun et al., Phys. Rev.

Effects of Persimmon Tannin- Composite on Cytotoxic Activities, and Radioprotection Against X-rays Irradiated in Human Hepatoma and Hepatic Cells.

A persimmon tannin- composite powder (PT-A) was investigated for its capacity to protect against ionizing radiation. Human hepatic cells (L02 cells) and human hepatoma cells (HepG2 cells) were pretreated with different concentrations of PT-A or the single compounds (PT or ) and radiated with X-rays. After radiation and post-incubation for 12 h or 24 h, the cell viability, apoptosis, and reactive oxygen species (ROS) production were analyzed by Cell Counting Kit 8 (CCK-8), 2',7'-dichlorfluorescein diacetate (DCFH-DA) staining, and Hoechst 33258 staining/flow cytometry, respectively.

rSCAN-D4: Dispersion corrected meta-generalized gradient approximation for general chemical applications.

We combine a regularized variant of the strongly constrained and appropriately normed semilocal density functional [J. Sun, A. Ruzsinszky, and J.

Accurate and Numerically Efficient rSCAN Meta-Generalized Gradient Approximation.

The recently proposed rSCAN functional [ 2019 150, 161101] is a regularized form of the SCAN functional [ 2015 115, 036402] that improves SCAN's numerical performance at the expense of breaking constraints known from the exact exchange-correlation functional. We construct a new meta-generalized gradient approximation by restoring exact constraint adherence to rSCAN. The resulting functional maintains rSCAN's numerical performance while restoring the transferable accuracy of SCAN.

Examining the order-of-limits problem and lattice constant performance of the Tao-Mo functional.

In their recent communication, Tao and Mo [Phys. Rev. Lett.

Protecting HaCaT cells from ionizing radiation using persimmon tannin- gel composite.

Persimmon tannin (extract of L.f [Ebenaceae]) and gel extract of (L.) Burm.

Efficient adsorption of methylene blue from aqueous solution by graphene oxide modified persimmon tannins.

With the rapid development of dye and textile industry, the pollution of dye wastewater has aroused widespread public concern due to the potential risk to human health. Therefore, it is of significance for the removal of dye pollutants from wastewater. In this work, a green and efficient bio-adsorbent, graphene oxide modified persimmon tannin (PT-GO), has been fabricated through glutaraldehyde crosslinking method for efficient adsorption of methylene blue (MB) from aqueous solutions.

Composition-induced type I and direct bandgap transition metal dichalcogenides alloy vertical heterojunctions.

While members of the 2D semiconducting transition metal dichalcogenide (TMD) family MX (M = {Mo, W}, X = {S, Se}) are promising for device applications, stacked layer (vertical) heterojunctions exhibit features that make them inappropriate for light-emitting applications. Such vertical heterojunctions exhibit type II, rather than the preferred type I band alignment. Using density functional theory calculations, we identify the pseudo-binary and quaternary alloy composition range for which band alignment is type I.

Pressure-induced pseudoatom bonding collapse and isosymmetric phase transition in Zr2Cu: first-principles predictions.

The structural evolution of tetragonal Zr2Cu has been investigated under high pressures up to 70 GPa by means of density functional theory. Our calculations predict a pressure-induced isosymmetric transition where the tetragonal symmetry (I4/mmm) is retained during the entire compression as well as decompression process while its axial ratio (c/a) undergoes a transition from ~3.5 to ~4.