Structural, elastic and thermodynamic properties of tetragonal and orthorhombic polymorphs of Sr2GeN2: an ab initio investigation

The present research utilizes ab initio computations to examine the thermodynamic, structural, and elastic characteristics of XAgO ternary oxides, where X signifies Li, Na, K, and Rb. The GGA-PBE and GGA-WC functionals were used to calculate the ground-state lattice parameters and atomic position coordinates of the title materials. The calculated results were in good agreement with both experimental measurements and theoretical predictions. This suggests that the GGA-PBE and GGA-WC functionals are accurate for describing the structural properties of the material under study. This study offers computational predictions for the elastic properties of monocrystalline structures and polycrystalline aggregates of XAgO compounds. These predictions encompass various key parameters, including single-crystal elastic constants, Young's modulus, bulk modulus, Lame coefficients, Poisson's ratio, shear modulus, and Debye temperature. Additionally, the quasi-harmonic Debye approximation is utilized to explore the temperature-dependent behavior of bulk modulus, Debye temperature, volume thermal expansion coefficient, and isobaric and isochoric heat capacities over an extensive temperature range, while maintaining constant pressures. The results obtained from this model are found to be highly successful in accurately predicting the behavior of these properties.

Section: Elasticity Characteristics 321 Elastic Constants Of the Mono...mentioning

confidence: 94%

Ab initio investigation of structural, elastic, and thermodynamic characteristics of tetragonal XAgO compounds (X = Li, Na, K, Rb)

Allali,

Amari,

Bouhemadou

et al. 2023

“…(vii) Microcracks are tiny fissures that develop in materials under stress, and if not addressed, these cracks can spread, ultimately leading to the mechanical failure or fracture of the material. Materials with pronounced elastic anisotropy are more susceptible to the development of microcracks and subsequent mechanical failure [42]. Various metrics have been devised to evaluate the degree of elastic anisotropy in materials.…”

Section: Elastic Properties 321 Single-crystal Elastic Constants and ...mentioning

confidence: 99%

Computational investigation of the structural, elastic, electronic, and thermodynamic properties of chloroperovskites GaXCl₃ (X = Be, Ca, or Sr) using DFT framework

Radjai,

Saad Essaoud,

Bouhemadou

et al. 2024

In this study, we employed the pseudopotential plane wave approach to examine the influence of the X atom (X = Be, Ca, or Sr) on the physical properties of isostructural chloroperovskites GaXCl3. The GGA-PBEsol and LDA functionals were employed to simulate the exchange-correlation interactions. The computed equilibrium lattice parameters exhibit a high level of concordance with the existing theoretical findings. The cohesion energy and enthalpy of formation were computed to verify the energetic stability of the materials under consideration. The determined values of the single-crystal elastic constants (Cij) indicate that GaBeCl3 remains mechanically stable up to a hydrostatic pressure of 18 GPa. Similarly, GaCaCl3 preserves its stability up to 5 GPa, while GaSrCl3 remains mechanically stable up to 1.25 GPa. The projected Cij values were used to estimate several elastic moduli and related properties, including the shear and bulk moduli, sound wave speeds, Young's modulus, Poisson's ratio, and Debye temperature. The quasiharmonic Debye approach was employed to examine various thermal parameters, including the temperature dependence of the unit cell volume, bulk modulus, expansion coefficient, Debye temperature, isochoric and isobar heat capacities, Grüneisen parameter, and entropy function. It has been shown that GaBeCl3 demonstrates a lower thermal expansion coefficient and a higher Debye temperature in comparison to GaCaCl3 and GaSrCl3.

“…It is interesting to know about the interaction of light with matter in different ways like reflection, absorption, emission, scattering and transmission. The optical characteristics are useful for investigating the impurity level, energy band structure, lattice vibration and localized defects [29]. The optical characteristics can be derived from the frequency dependent dielectric function which can be defined as:…”

Section: Optical Propertiesmentioning

confidence: 99%

DFT study of the structural, elastic and optoelectronic properties of Cu-based cubic halide-perovskites ACuF₃ (A = Mg and Ca)

Abdullah¹,

Khan²,

Ullah³

et al. 2022

Copper based halide-perovskites ACuF3 (A= Mg and Ca) have been studied for potential application as an electrode material. Structural, electronic, elastic and optical properties of these compounds are investigated by utilizing the wien2k code within density functional theory. Structural study reveal that both compounds have stable and cubic perovskite structure with optimized lattice constants 4.07 Å and 4.15 Å having space group pm-3m 221. Electronic analysis reveals that both compounds have metallic nature. Through IR-Elast package the elastic constants are evaluated and by utilizing these constant various elastic parameters like bulk modulus, shear modulus, Kleinman parameter, Anistropic factor are analyzed. Both compounds are found to be mechanically stable with ductile nature. Furthermore, the various optical parameters such as dielectric function, refractive index, optical conductivity, reflectivity and absorption coefficient are studied. The seebeck coefficient, thermal conductivity and figure of merit are studied through BoltzTrap. The study reveals that MgCuF3 and CaCuF3 can be potential candidates for electrode materials.