相关论文: Phase Separation in Li$_x$FePO$_4$ Induced by Corr…

First-principles calculations within the Local Density Approximation (LDA) or Generalized Gradient Approximation (GGA), though very successful, are known to underestimate redox potentials, such as those at which lithium intercalates in…

Predicting the compositional phase stability of strongly correlated electron materials is an outstanding challenge in condensed matter physics. In this work, we employ the DFT+U formalism to address the effects of local correlations due to…

The transmission electron microscopy observations of the charge ordering (CO) which governs the electronic polarization in LuFe2O4-x clearly show the presence of a remarkable phase separation at low temperatures. Two CO ground states are…

We demonstrate that configurational electronic entropy, previously neglected, in {\it ab initio} thermodynamics of materials can qualitatively modify the finite-temperature phase stability of mixed-valence oxides. While transformations from…

Previous first-principles calculations of the melting properties of Si, based on the local-density approximation (LDA) for electronic exchange-correlation energy, under-predict the melting temperature by ~ 20%. We present new…

The theory of phase stability in the Ni-Au alloy system is a popular topic due to the large size mismatch between Ni and Au, which makes the effects of atomic relaxation critical, and also the fact that Ni-Au exhibits a phase separation…

The phase separation behaviors from the single B2 ordered phase into the two separate B2 and L2$_1$ ordered phases in the X-Al-Ti (X: Fe, Co, and Ni) alloys are analyzed using the cluster variation method (CVM) with the interaction energies…

Lithium iron phosphate (LiFePO$_4$) is the prototypical two-phase battery material, whose complex patterns of lithium ion intercalation provide a testing ground for theories of electrochemical thermodynamics. Using a depth-averaged (a-b…

We discover presence of chemical inductive effects in phase separating ion intercalation energy storage materials, specifically in lithium iron phosphate (LFP) and also lithium titanate oxide (LTO). These materials features fast…

In ab initio pseudopotential calculations within density-functional theory the nonlinear exchange-correlation interaction between valence and core electrons is often treated linearly through the pseudopotential. We discuss the accuracy and…

We study the thermodynamic behavior of nonpolar liquid mixtures in the vicinity of curved charged objects, such as electrodes or charged colloids. For small enough charge on the object, or equivalently, small potential, the…

The generalized gradient approximation (GGA) scheme in the first-principles calculations are used to study the effect of L21 and XA ordering on the phase stability, half-metallicity and magnetism of Co2FeAl (CFA) Heusler alloy. Various…

Employing the $G_0W_0$ approximation of Hedin's $GW$ approach one can obtain quasi-particle energies of extended systems and molecules with good accuracy. However, for many materials, semi-local exchange-correlation functionals are…

Lithium intercalated anatase used in Li-ion batteries has some special features: coexistence of Li-rich and Li-poor phases as well as two possible positions for Li ions in the oxygen tetrahedron. A theoretical description of the compound…

Oxygen plays a critical role in strongly correlated transition metal oxides as crystal field effect is one of the key factors that determine the degree of localization of the valence d/f states. Based on the localization, a set of…

There is growing evidence that the unconventional spatial inhomogeneities in the doped high-Tc superconductors are accompanied by the pairing of electrons, subsequent quantum phase transitions (QPTs), and condensation in coherent states. We…

First principles density functional theory calculations within the GGA+U approximation were performed for LiMn$_{1-x}$M$_x$O$_{2}$, a candidate cathode material for lithium-ion batteries, with ($x=0.25$, M=Ni, Fe, Co, Mg), to investigate…

First principle calculations based on LDA/GGA approximation for the exchange functional underestimate the position of the semi core 3d levels in GaX (X = N, P and As) semiconductors. A self-interaction correction scheme within the…

We consider the effects of anisotropic coherency strain (due to lattice mismatch) on phase separation in intercalation materials, motivated by the high-rate Li-ion battery material \fepo. Using a phase-field model coupled to elastic…

Our study of FeSe$ _ {1-x}$Te$ _ {x}$ crystals with x $<$ 0.15 shows that the phase separation in these compositions occurs into phases with a different stoichiometry of iron. This phase separation may indicate structural instability of the…