We have presented the structural, elastic, optoelectronic and transport properties of Sr3SnO under pressure by using first principles method. The application of hydrostatic pressure causes charge transfer from Sr(5s) orbital to Sn(5p) and O(2p) orbitals. The increasing trend of Pughs ratio under pressure implies that the material tends to be ductile at high pressure. The semiconductor-metal transition occurs at 14 GPa and the density of states at the Fermi level is significantly increased at this pressure. The refractive index, optical conductivity, and absorption of Sr3SnO have been found to be high and comparable to that for typical materials used in photovoltaic. The material becomes n-type from 12 GPa and Hall coefficient also confirm it. Large Seebeck coefficient obtained at 12 GPa. Thus, Sr3SnO is a potential thermoelectric material possessing both p- and n-type nature. The detail physics of these changes under pressure has been explained within the available theory.
Transition metal dichalcogenides (TMDCs) belong to technologically important compounds. We have explored the structural, elastic, bonding, optoelectronic and some thermo-physical properties of ZrX2 (X = S, Se, Te) TMDCs in details via ab-initio technique in this study. Elastic anisotropy indices, atomic bonding character, optoelectronic properties and thermo-physical parameters including melting temperature and minimum phonon thermal conductivity are investigated for the first time. All the TMDCs under investigation possess significant elastic anisotropy and layered structural features. ZrX2 (…
Inorganic metal-halide cubic perovskite semiconductors have become more popular in industrial applications of photovoltaic and optoelectronic devices. Among various perovskites, lead-free materials are currently most explored due to their non-toxic effect on the environment. In this study, the structural, electronic, optical, and mechanical properties of lead-free cubic perovskite materials FrBX3 (B = Ge, Sn; X = Cl, Br, I) are investigated through first-principles density-functional theory (DFT) calculations. These materials are found to exhibit semiconducting behavior with direct bandgap ene…
Computational study of structural, elastic, electronic, phonon dispersion relation and thermodynamic properties of orthorhombic CaZrS$_3$ for optoelectronic applications
We present a detailed density functional theory based calculations of the structural, elastic, lattice dynamical, thermophysical, and optoelectronic properties of ternary semiconductors CaZn$_2$X$_2$ (X = N, P, As) in this paper. The obtained lattice parameters are in excellent agreement with the experimental values and other theoretical findings. These elastic constants satisfy the mechanical stability criteria. Moreover, many thermophysical parameters of these compounds are estimated, including the Debye temperature, average sound velocity, melting temperature, heat capacity, lattice thermal…
Binary carbides demonstrate attractive set of physical properties that are suitable for numerous and diverse applications. In the present study, we have explored the structural properties, electronic structures, elastic constants, acoustic behaviors, phonon dispersions, optical properties, and various thermophysical properties of binary orthogonal and hexagonal Mo2C compounds in details via first-principles calculations using the density functional theory (DFT). The calculated ground state lattice parameters in both the symmetries are in excellent agreement with available experimental results.…
Pressure-Driven Phase Evolution and Optoelectronic Properties of Lead-free Halide Perovskite Rb$_2$TeBr$_6$
Indian Institute of Science Education and Research Kolkata(印度科学教育研究学院加尔各答分校);National Centre for High Pressure Studies, Indian Institute of Science Education and Research Kolkata(印度科学教育研究学院加尔各答分校高压研究中心);Elettra-Sincrotrone Trieste S.C.p.A.(的里雅斯特电子同步辐射中心)
PbTaSe2 is a non-centrosymmetric topological semimetal. In this work we have explored the structural, elastic, mechanical, bonding, electronic, acoustic, thermal, and optical properties of PbTaSe2. The electronic bond structure calculations confirm semi-metallic character. Fermi surface topology shows both electron and hole sheets. The single crystal elastic constants reveal that PbTaSe2 is elastically stable. The compound is soft, brittle, and highly machinable at the same time. It also possesses very high level of dry lubricity. Various anisotropy indicators suggest that PbTaSe2 is elastical…
Optical and electrical properties of two-dimensional transition metal dichalcogenides (TMDCs) grown by chemical vapor deposition (CVD) are strongly determined by their microstructure. Consequently, the visualization of spatial structural variations is of paramount importance for future applications. Here we demonstrate how grain boundaries, crystal orientation, and strain fields can unambiguously be identified with combined lateral force microscopy (LFM) and transverse shear microscopy (TSM) for CVD-grown tungsten disulfide (WS2) monolayers, on length scales that are relevant for optoelectroni…
In the present study we have investigated the structural properties, electronic band dispersion, elastic constants, acoustic behavior, phonon spectrum, optical properties, and a number of thermophysical parameters of binary topological semimetal BaGa2 in details via first-principles calculations using the density functional theory (DFT) based formalisms. The electronic band structure and density of states calculations with spin orbit coupling reveal semimetallic nature with clear topological signature. The minimum thermal conductivities and anisotropies of the compound are calculated. The elas…
High-Pressure DFT Study of BeX (X = S, Se, Te): Phonon Spectra, Optical Properties, and Thermodynamic Stability for Advanced Optoelectronic Applications
SnTaS2 is a recently discovered layered semimetal exhibiting type-II low transition temperature superconductivity. Except some superconductivity related parameters, most of the physical properties, namely, elastic, mechanical, bonding, phonon dispersion, acoustic, thermophysical, and optical properties of SnTaS2 are unexplored till now. In this study, we have investigated these hitherto unexplored properties of SnTaS2 for the first time employing density functional theory (DFT) based first-principles method. SnTaS2 is a mechanically stable, elastically anisotropic compound with strongly layere…
In this paper, we did a systematic comparative study on the accuracy of two computational methods of elastic constants combined with the density functional theory (DFT), the stress-strain method and the energy-strain method. We took metal Ru as a prototype to compare its high-pressure elastic constants calculated by our present stress-strain method with the previous energy-strain results by others. Although the two methods yielded almost the same accuracy of high-pressure elastic constants for Ru, our stress-strain method directly based on the Hooke's law of elasticity theory is much straightf…
The speed of sound and elastic properties of single crystals of inorganic and hybrid lead-free iodide perovskites obtained by femtosecond transient optical reflectivity
On some extreme cohesive properties of alpha-Plutonium: temperature dependence of elastic moduli, large pressure derivative of bulk modulus and Grūneisen parameter
Pressure induced structural transitions, coordination crossover, and optoelectronic response in divalent metavanadate CaV$_2$O$_6$
Indian Institute of Science Education and Research Kolkata(印度科学教育研究学院加尔各答分校);National Centre for High-Pressure Studies(高压研究中心);IMPMC, Sorbonne Université(巴黎第六大学地球物理学研究所);Beijing Academy of Quantum Information Sciences(北京量子信息科学研究院);Deutsches Elektronen Synchrotron(德国电子同步辐射中心)
First Principal Investigations to Explore the Half-metallicity, Structural, Mechanical, and Optoelectronic Properties of Sodium-Based Fluoroperovskites NaYF3 (Y = Sc and Ti) for Applications in Spintronics and Optoelectronics
Td-WTe2 is a topological Weyl semimetal. WTe2 in the orthorhombic structure is stable at room temperature. Elastic, electronic, bonding, and optoelectronic properties of WTe2 have been investigated in detail in this work using the density functional theory. Elastic behaviour together with anisotropy indices of WTe2 have been investigated for the first time. Bonding nature among the constituent atoms and electric field polarization dependent optical constants have also been explored for the first time. WTe2 is elastically anisotropic; optical anisotropy on the other hand is low. The electronic …
DFT based investigation of structural, elastic, optoelectronic, thermophysical and superconducting state properties of binary Mo3P at different pressures
Comment on "On the importance of the free energy for elasticity under pressure"
Marcus等人(Marcus P,Ma H和Qiu S L 2002 J. Phys.:康登斯Matter 14 L525)声称,在压力下材料的热力学性质必须使用吉布斯自由能$G$计算,而不是内能$E$。Marcus等人指出,"$G$而不是$E$的最小值给出了平衡结构; $G$而不是$E$相对于平衡结构处的应变的二阶导数给出了平衡弹性常数。“这两种说法都不正确。
Density functional theory based study of the pressure dependent physical properties of binary SnS compound has been carried out. The computed elastic constants reveal that SnS is mechanically stable and brittle under ambient conditions. With increasing pressure, the compound becomes ductile. The Poisson's ratio also indicates brittle-ductile transition with increasing pressure. The hardness of SnS increases significantly with pressure. The compound possesses elastic anisotropy. The ground state electronic band structure is semiconducting with a small band gap which becomes metallic under press…
Applying elastic deformation can tune a material physical properties locally and reversibly. Spatially modulated lattice deformation can create a bandgap gradient, favouring photo-generated charge separation and collection in optoelectronic devices. These advantages are hindered by the maximum elastic strain that a material can withstand before breaking. Nanomaterials derived by exfoliating transition metal dichalcogenides TMDs are an ideal playground for elastic deformation, as they can sustain large elastic strains, up to a few percent. However, exfoliable TMDs with highly strain-tunable pro…
Mechanical properties of transition metal dichalcogenides (TMDCs) are relevant to their prospective applications in flexible electronics. So far, the focus has been on the semiconducting TMDCs, mostly MoX2 and WX2 (X=S, Se) due to their potential in optoelectronics. A comprehensive understanding of the elastic properties of metallic TMDCs is needed to complement the semiconducting TMDCs in flexible optoelectronics. Thus, mechanical testing of metallic TMDCs is pertinent to the realization of the applications. Here, we report on the atomic force microscopy-based nano-indentation measurements on…
Beta-PtO2 is a useful transition metal dioxide, but its fundamental thermodynamic and elastic properties remain unexplored. Using first-principles calculations, we systematically studied the structure, phonon, thermodynamic and elastic properties of beta-PtO2. The lattice dynamics and structural stability of beta-PtO2 under pressure were studied using the phonon spectra and vibrational density of states. The vibrational frequencies of the optical modes of beta-PtO2 increase with elevating pressure; this result is comparable with the available experimental data. Then, the heat capacities and th…
In an outstanding experimental advance in the field of two-dimensional nanomaterials, cuprous iodide (CuI) and silver iodide (AgI) monolayers have been grown via a novel graphene encapsulation synthesis approach [Adv.Mater.2022, 34, 2106922]. Inspired by this accomplishment, we conduct first-principles calculations to investigate the elastic, phononic thermal transport, electronic, and optical properties of the native CuI and AgI and Janus Cu2BrI and Ag2BrI monolayers. Electronic and excitonic optical properties are elaborately studied using the many-body perturbation theory on the basis of GW…
First-principles calculations using the plane-wave pseudopotential method within the generalized gradient approximation method were performed to study the pressure dependence of the structural, elastic, electronic and optical properties for the half-Heusler compounds ScPtSb and YPtSb in a cubic MgAgAs-type structure. The calculations were performed with the inclusion of spin-orbit coupling. The calculated equilibrium lattice parameters are in good agreement with the available experimental and theoretical values. The crystal rigidity and mechanical stability were discussed using the elastic con…