Murnaghan Equation Research Articles

Charge transfer induced phase transition in Li2MnO3 at high pressure

Efficient and better energy storage materials are of utmost technological importance to reduce energy dependence on the fossil fuels. Li2MnO3is one such material having potential to meet most of the requirements for energy storage. This material has been synthesized using solid state synthesis route. High pressure structural and vibrational studies on this material have been carried out upto ∼22 and 26 GPa respectively. These investigations show occurrence of a hitherto unknown second order phase transition to a new low symmetry phase whose symmetry is constrained to be monoclinic with space group P21/n at pressure of ∼2.3 GPa in Li2MnO3. The bulk modulus and its derivative determined by fitting theP-Vdata with third order Birch-Murnaghan equation of state are 113.3 ± 13.1 GPa and 4.1 ± 1.2 respectively. Mode Grüneisen parameter calculated for all the Raman modes show positive values which indicates the absence of any soft mode in this material. A microscopic mechanism based on bond-charge transfer is invoked and applied to understand the spectroscopic changes occurring in this material which also manifests second order structural phase transition. Enhancement in covalent character of Li-O bonds in the Li-O polyhedra is inferred based on the spectroscopic observation and above mechanism.

Investigation of the behaviour of tunable chalcogenide-Bismuth based perovskite BiTl (SxSe1-x)3(X = 0, 0.33, 0.67, 1): first principles calculations

Density functional theory (DFT) driven by the quantum ESPRESSO code was used in this study to investigate the structural, opto-electronic, and thermoelectric properties of ternary perovskite chalcogenide compound. This is to examine their possible use in optoelectronics and reducing the dependency on silicon and fossil fuel. The Perovskite compounds crystalize in the cubic phase with a space group Pm-3m. The volume versus energy is fitted by the Birch-Murnaghan equation of state which yielded the equilibrium lattice constant of 8.353, 8.488, 8.629 and 8.806, bulk modulus of 255.8, 242.7, 233.5 and 222.4, for BiTlS3 , BiTlS2 Se1 , BiTlS1 Se2 and BiTlSe3 . Indirect band gaps of 2.6 eV, 2.7 eV, 2.9 eV, and 3.2 eV were obtained for BiTlS3 , BiTlS2 Se1 , BiTlS1 Se2 and BiTlSe3 compounds, respectively. Also, increment in the energy from 0 eV to 10 eV resulted in optical properties fluctuation within 0 cm-1 to 1.5 × 109 cm-1 for absorption coefficient in the compounds. However, a variation from 10 eV to 20 eV moved the absorption coefficient to 4.2 × 109 cm-1 for all the compounds from visible to the UV range. Furthermore, the observed properties show that the value of figure of merit obtained is 0.125 for BiTlS3 , 0.100 for BiTlS2 Se1 , 0.068 for BiTlS1 Se2 and 0.055 for BiTlSe3 at 300 K. By adjusting the chalcogen ratio, BiTlX3 (X = S, Se) possess the tunable band gap in the whole visible light range, which is of great significance for the development of new-type, high-efficient semiconductor material and optoelectronic devices, while the low thermoelectric values predict the compounds use as sensors. The proposed results may pave the way for further investigations into the use of the perovskite compounds for optoelectronic devices.

Biaxial and Uniaxial Strain Effect on Structural and Electronic Properties of Anatase TiO<sub>2</sub>: A First-Principle Calculation

The effect of biaxial and uniaxial strains on the electronic structure of anatase is studied using Density Functional Theory (DFT) calculation with ultrasoft pseudopotential and a generalized gradient approximation (GGA) Perdew-Burke Ernzerhof (PBE) exchange-correlation. The lattice constant is optimized using the Birch-Murnaghan equation of states (BM-EOS) to get an optimized geometric structure of anatase TiO2. We apply biaxial and uniaxial strains to this optimized structure up to 16% and find that the applied strains change the band gap energy compared to a pure anatase with a different band gap energy up to 1.61 eV for biaxial strain and 0.35 eV for uniaxial strain. The biaxial strains increase gap energies except at +16% tensile strain, decreasing the gap energy to 0.04 eV. Uniaxial strains tend to increase as the strains increase except at-12 and-16%; their gap energy differences are 0.08 and 0.20 eV, respectively, smaller than that of the zero strain. The results also show that the applied 16% tensile strain significantly lengthens the atomic bonds; thus, we conclude that the maximum strain applied to anatase TiO2 is 16%.

Revealing the Response of Structure and Decomposition Behaviors of 1, 1′‐Azobis‐1, 2, 3‐Triazole to Pressure: A Theoretical Study

ABSTRACT1, 1′‐azobis‐1, 2, 3‐triazole (C4H4N8, N8) is a novel nitrogen‐rich energetic material with excellent detonation performance, which has received widespread interest. Inspired by recent theories and experiments, the dependence of structural, vibrational, and electronic properties on high pressure up to 10 GPa was systematically investigated using periodic DFT calculations. It was found that the optimized structure belonged to the cis‐N8 structure through comparing the theoretical IR with experimental IR spectra. The third‐order Birch–Murnaghan equation of state for N8 was obtained up to 10 GPa, where the bulk modulus and its pressure derivative were 10.91 GPa and 7.689, respectively. More importantly, the pressure dependence of Laplacian bond order indicated that the five‐membered ring opening was the first step in the decomposition process, and that high pressure could inhibit the decomposition process of N8 due to the reinforcement of non‐covalent interactions. The present work could deepen the understanding of the energetic materials N8 under high pressure, and is of great significance to the blasting and detonation applications of N8.

Harnessing the half-metallicity and thermoelectric insights in Cs2AgMBr6 (M = V, Mn, Ni) double halide perovskites: A DFT study

Herein, we undertake a detailed exploration of the structural stability, magneto-electronic behavior, and thermoelectric properties of Cs₂AgMBr₆ (M = V, Mn, Ni) halide double perovskites using first-principles approach. The study commences with a meticulous assessment of both structural stability and thermodynamic properties employing various metrics. Energy minimization across different phases, utilizing the Birch-Murnaghan equation of state, confirms the ferromagnetic phase as energetically favoured, supported by Curie-Weiss constants of 98 K, 100 K, and 150 K for V, Mn, and Ni-based perovskites, respectively. Mechanical properties, including hardness, stiffness, ductility, and fracture strength, are derived from the simulated elastic constants, ensuring the mechanical stability of the materials. Electronic structure analysis, performed using the PBE-GGA and GGA + mBJ functionals, reveals that Cs₂AgMBr₆ compounds exhibit half-metallic ferromagnetism, with 100 % spin polarization at the Fermi level. Analysis of the partial density of states highlights the half-metallic ferromagnetic mechanism, confirming predominant ferromagnetic order through parameters such as the exchange splitting energy (Δx), p-d exchange interaction energy (Δx(p-d)), crystal-field energy (Ecrys), and exchange constants (N₀α and N₀β). The negative values of the exchange constants further validated the dominant ferromagnetic order in both s-d and p-d interactions, with unpaired electrons contributing magnetic moments of 2 μB for V, 4 μB for Mn, and 1 μB for Ni-based perovskites. Also, the Curie temperatures are calculated as 385 K, 747 K, and 204 K for V, Mn, and Ni-based perovskites. The overall findings, which reveal 100 % spin polarization and high zT values, underscore the significant potential of Cs₂AgMBr₆ halide perovskites for advancing spintronics and thermoelectric applications.

A Proposal of an Isothermal q-EoS for Solids at High Pressures

We present a new approach to the isothermal equation of state for solids when subjected to high pressures. The central point lies in the fact that the solid subjected to high pressures presents non-linear elastic behavior. We show how the connection between the q-deformed finite deformation theory and the mathematical formalism of Non-Extensive Statistical Mechanics, as postulated by Tsallis [1], allows us to achieve a q-deformed equation of state. We also establish the associated q-deformed interatomic potential and discuss its relation to the Grüneisen parameter.

Influence of cation disorder on the mineral physics of ankerite

Abstract The structural evolution and compressibility of ordered and disordered ankerite at pressures up to ~25 GPa using synchrotron single crystal X-ray diffraction in diamond anvil cell was analyzed. Ordered ankerite (space group R3) undergoes discontinuous phase transition between 12.15 and 13.45 GPa to a high-pressure structure called ankerite-II (space group P1) that has Ca in eight-fold coordination. Disordered ankerite (R3c space group) does not undergo a phase transition in the investigated pressure range. A Birch-Murnaghan equation of state has been used to fit the volume compressibility. Ordered ankerite [K0V=95(1) GPa - K’=3.8(3)] appears slightly more compressible than disordered ankerite [K0V=99(1) GPa - K’=2.7(1)]. The phase transition in ordered ankerite has a change in volume of approximately 0.6% and K13.45V=110(11) GPa - K’=7(3) for ankerite-II. The possible significance of this differential behavior of ordered and disordered ankerite is discussed.

Exploring Rb2YCuCl6 and Cs2YCuCl6 double perovskites: Structural, electronic, optical, elastic, and thermoelectric properties via density functional theory

Double perovskites have gathered momentous attention due to their structural, optoelectronics, and thermal properties. FP-LAPW + lo technique was employed along with the PBEsol-GGA and TB-mBJ potential. The optimized parameters and E-V parabolic curve were computed employing Birch Murnaghan's equation of state (BM-EOS). The negative formation energy Ef for Rb2YCuCl6 and Cs2YCuCl6 confirms the thermodynamic stability of these double perovskites. The mechanical stability of both compounds was confirmed by their elastic constants Cij, Pugh's ratio, and anisotropy. The indirect band plots of Rb2YCuCl6 (2.57eV) and Cs2YCuCl6 (2.39eV) double perovskites confirm the semiconductor nature. The optical properties like dielectric function, reflectivity, optical conductivity, absorption coefficient, and energy loss function were determined within an energy range of up to 18 eV. The high absorption spectra for the under-study compounds 147.21 × 104 cm−1 at 14.60 eV for Rb2YCuCl6 and 261.30 × 104 cm−1 at 15.57 eV for Cs2YCuCl6 lies in the far UV region determines its potential use in the high-frequency devices. The thermoelectric properties such as the Seebeck coefficient, ZT, and power factor, are investigated using the semi-classical Boltzmann theory implemented in the BoltzTrap code. The peak value of ZT for Rb2YCuCl6 is 0.38 and for Cs2YCuCl6 is 0.33. The suggested findings indicate that Rb2YCuCl6 and Cs2YCuCl6 are potential candidates for thermoelectric and photovoltaic applications.

Insights into Ag2Mo3SeO12 for photovoltaic and optoelectronic applications: A theoretical exploration of its structural, electronic, and thermoelectric behavior

The theoretical investigation of the newly discovered quadruple perovskite Ag₂Mo₃SeO₁₂ was conducted using density functional theory (DFT) with the generalized gradient approximation (GGA-PBE) for the structural properties. This study examined the compound's structural, electronic, optical, and thermoelectric properties, utilizing the Tran Blaha modified Becke-Johnson exchange potential (mBJ) for accurate band gap measurement to overcome the bandgap underestimation by GGA-PBE. The stable structure was confirmed through energy-volume optimization and fitted with the Birch-Murnaghan equation of state, using PBE-GGA exchange correlation functional. The findings revealed a band structure with direct transition under the TB-mBJ approach with an energy gap of 1.45 eV. Detailed analyses were conducted, including the density of states and charge density distribution maps. Various optical parameters such as the dielectric function, absorption coefficient, refractive index, and reflectivity were computed, with the static dielectric constant measured at 6.3. Notably, a significant evolution of the absorption coefficient in the visible region highlights the potential of Ag₂Mo₃SeO₁₂ for solar cell and optoelectronic applications. These results pave the way for new photovoltaic material designs. Furthermore, the material demonstrates promising thermoelectric properties with an appropriate figure of merit, Seebeck coefficient, and electrical and thermal conductivity evolution under different temperature conditions, indicating its potential for photovoltaic and optoelectronic applications.

Comprehensive analysis of structural, mechanical, optoelectronic, and thermodynamic properties of Ba2XBiO6 (X = Y, La) double perovskites using density functional theory

The structural, mechanical, optoelectronic, and thermodynamic properties of Ba2XBiO6 (X = Y, La) double perovskites are critically analyzed using density functional theory. The Birch-Murnaghan equation of state confirms their structural stability, supported by tolerance factor analysis. For Ba2YBiO6 and Ba2LaBiO6, negative formation energies are −0.935 eV for Ba2YBiO6 and −0.836 eV for Ba2LaBiO6, confirming thermodynamic stability. Phonon dispersion curves indicate stable lattice vibrations, reducing the likelihood of spontaneous structural changes or phase transitions. Ba2YBiO6 possesses higher elastic constants C 11 = 222 GPa shows stiffness and exhibits brittle mechanical behavior, whereas the Pugh ratio and C 11 = 217 GPa for Ba2LaBiO6 shows ductility. The Poisson ratio classifies Ba2YBiO6 as a non-central force crystal and Ba2LaBiO6 as a central force crystal. Both materials are indirect band gap semiconductors, with band gap values of 0.75 eV for Ba2YBiO6 and 2.05 eV for Ba2LaBiO6. Optical properties suggest applications in UV and visible light-based optoelectronic devices. Thermodynamic properties, such as Debye temperature and heat capacity, support the idea that these materials are suitable for high mechanical applications. These findings provide insights for designing high-performance optoelectronic and mechanical devices.

Generally applicable physics-based equation of state for liquids

Physics-based first-principles pressure-volume-temperature equations of state (EOS) exist for solids and gases but not for liquids due to the long-standing fundamental problems involved in liquid theory. Current EOS models that are applicable to liquids and supercritical fluids at liquid-like density under conditions relevant to planetary interiors and industrial processes are complex empirical models with many physically meaningless adjustable parameters. Here, we develop a generally applicable physics-based (GAP) EOS for liquids including supercritical fluids at liquid-like density. The GAP equation is explicit in the internal energy, and hence links the most fundamental macroscopic static property of fluids, the pressure-volume-temperature EOS, to their key microscopic property: the molecular hopping frequency or liquid relaxation time, from which the internal energy can be obtained. We test our GAP equation against available experimental data in several different ways and find good agreement. Our GAP equation, unavoidably and similarly to solid EOS, contains a semi-empirical term giving the energy of the static sample as a function of volume only (EST(V)). Our testing includes studies along isochores, in order to examine the validity of the GAP equation independently of the validity of any function we may choose to utilize forEST(V). The only other adjustable parameter in the equation is the Grüneisen parameter for the fluid. We observe that the GAP equation is similar to the Mie-Grüneisen solid EOS in a wide range of the liquid phase diagram. This similarity is ultimately related to the condensed state of these two phases. On the other hand, the differences between the GAP equation and EOS for gases are fundamental. Finally, we identify the key gaps in the experimental data that need to be filled in to proceed further with the liquid EOS.

All-optical method to directly measure the pressure–volume–temperature equation of state of fluids in the diamond anvil cell

We have developed a new all-optical method to directly measure the pressure–volume–temperature (PVT) equation of state (EOS) of fluids and transparent solids in the diamond anvil high pressure cell by measuring the volume of the sample chamber. Our method combines confocal microscopy and white light interference with a new analysis method, which exploits the mutual dependence of sample density and refractive index: Experimentally, the refractive index determines the measured sample chamber thickness (and therefore the measured sample volume/density), yet the sample density is by far the dominant factor in determining the variation in the refractive index with pressure. Our analysis method allows us to obtain a set of values for the density and refractive index, which are mutually consistent and agree with the experimental data within error. We have conducted proof-of-concept experiments on a variety of samples (H2O, CH4, C2H6, C3H8, KCl, and NaCl) at ambient temperature and at high temperatures up to just above 500 K. Our proof-of-concept data demonstrate that our method is able to reproduce known fluid and solid EOS within error. Furthermore, we demonstrate that our method allows us to directly and routinely measure the PVT EOS of simple fluids at GPa pressures up to, at least, 514 K (the highest temperature reached in our study). A reasonable estimation of the known sources of error in our volume determinations indicates that the error is currently ±2.7% at high temperature and that it is feasible to reduce it to ca. ±1% in future work.

Unraveling the structural and vibrational response of Zharchikhite to pressure (II): Insights from first principles calculations

The halide mineral Zharchikhite with the chemical formula AlF(OH)2 is studied using first-principles methods of density functional theory with the local functional VBH, generalized gradient functionals PBE, BLYP, PBEsol, with an empirical dispersion correction in the form of D3(BJ) PBE-D3, BLYP-D3, global hybrid functionals PBE0, B3LYP, PBEsol0, hybrid functionals with range separation HSE06, SC-BLYP. It is shown that all functionals overestimate O-H and underestimate O-H∙∙∙O distances. The best values are provided by SC-BLYP, B3LYP. The bulk modulus, determined from the Birch-Murnaghan equation of state, is 72.32 GPa. The axes compress unevenly and the fastest is the longest one with a modulus of 217.3 GPa. The linear compressibility modulus of the Al-F bond has a similar value and is twice as large for the Al-O bond. Under pressure, the lengths of H∙∙∙O hydrogen bonds decrease faster and, conversely, O-H bonds slowly increase. Also, at a rate of 0.289°/GPa, the monoclinic angle also increases with pressure. The spectra of infrared absorption and Raman scattering of light have been calculated, in which vibrations of Al-F and Al-O atoms were actived in the region up to 600 cm−1; above 700 cm−1 there are translational vibrations of O-H with a dominant contribution of H1 (Au symmetry) or H2 (Bu symmetry) and above 3200 cm−1 100 % hydrogen atoms. For them, with increasing pressure, the wave numbers decrease and the Grüneisen parameters change from −0.36 to −0.54. The large value of the derivative dν/dP can be used to solve the inverse problem - finding the pressure P from the known wave number ν(P).

Pressure-Induced Exciton Formation and Superconductivity in Platinum-Based Mineral Sperrylite.

We report a comprehensive study of Sperrylite (PtAs2), the main platinum source in natural minerals, as a function of applied pressures up to 150 GPa. While no structural phase transition is detected from pressure-dependent X-ray measurements, the unit cell volume shrinks monotonically with pressure following the third-order Birch-Murnaghan equation of state. The mildly semiconducting behavior found in pure synthesized crystals at ambient pressures becomes more insulating upon increasing the applied pressure before metalizing at higher pressures, giving way to the appearance of an abrupt decrease in resistance near 3 K at pressures above 92 GPa consistent with the onset of a superconducing phase. The pressure evolution of the calculated electronic band structure reveals the same physical trend as our transport measurements, with a non-monotonic evolution explained by a hole band that is pushed below the Fermi energy and an electron band that approaches it as a function of pressure, both reaching a touching point suggestive of an excitonic state. A Lifshitz transition of the electronic structure and an increase in the density of states may naturally explain the onset of superconductivity in this material.

Screening the structural, optoelectronic and thermoelectric features of novel inverse perovskites X3MgNa (X= Cl, Br and I): A theoretical investigation

The structural, optoelectronic, and transport features of novel X3MgNa (X = Cl, Br, and I) antiperovskites compounds are revealed by using the density functional theory. The structural stability of all of the compounds under consideration has been verified by using the Birch-Murnaghan equations of states, which indicate that all compounds have structural stability due to ground-state energy levels being negative. The electronic band structure and TDOS results reveal that the electronic band gap of Cl3MgNa is 4.22 eV, Br3MgNa is 2.18 eV, and I3MgNa is zero eV. The partial density of state PDOS results demonstrate that the formation of the conduction and valence bands is due to the hybridization of Cl-3p, Br-4p, Na-3p, and I-5p states. In terms of optical results, reverse perovskite with Br as a cation has shown much better optical conductivity in the ultraviolet range. Therefore, Br3MgNa is a potential candidate among all the compounds for optoelectronic-based applications. The Boltztrap code, which is patched with WEIN2K code, has been used to compute the thermoelectric characteristics of the examined compounds. Br3MgNa has a greater power factor, a high electrical conductivity, and a figure-of-merit; ZT approaches unity, indicating a promising option for thermoelectric applications.

Compressibility and pressure-induced structural evolution of kokchetavite, hexagonal polymorph of KAlSi3O8, by single-crystal X-ray diffraction

Abstract Compressibility and pressure-induced structural evolution of kokchetavite, the hexagonal polymorph of KAlSi3O8, has been studied up to 11.8 GPa using synchrotron single-crystal X-ray diffraction. Two phase transitions were observed at pressures of ~0.3 and 10.4 GPa. Kokchetavite-I (as-synthesized, P6/mcc) transforms into kokchetavite-II with the P6c2 space group. Kokchetavite-II → kokchetavite-III phase transition at ~10.4 GPa is accompanied by a change of symmetry to probably orthorhombic. After pressure release, kokchetavite reverts to the initial single-crystal state with P6/mcc space group. A second-order Birch-Murnaghan equation of state was calculated for phase kokchetavite-II with coefficients V0 = 1486(3) Å3, K0 = 59(2) GPa.

Theoretical profiling of chloroperovskite compounds GaXCl3 (X = Ba, Sr) using density functional theory

This study employs the TB-mBJ exchange potential within the WIEN2k code and DFT to comprehensively analyze GaXCl3 compounds (X = Sr, Ba). The investigation includes verifying perovskite structure and determining structural, elastic, electronic, and optical properties. Upon optimization with the Birch Murnaghan equation of state, GaScCl3 and GaBaCl3 exhibit a cubic crystal structure with lattice constants of 5.675 Å and 5.978 Å, respectively. The contribution of elemental states to valence and conduction bands is assessed using TDOS and PDOS features. GaSrCl3 and GaBaCl3 display indirect band gaps of 3.260 eV and 4.365 eV, respectively. Mechanical properties are explored with IRelast software. Optical features, including dielectric function, optical conductivity, reflectivity, refractive index, absorption coefficient, and energy loss function, show significant dependence on electromagnetic field energy. GaSrCl3 and GaBaCl3 exhibit static field refractive index values of 2 and 1.5, with maximum refractive indices of 2.4 at 3.7 eV and 2.2 at 7 eV, respectively. Both compounds record a maximum optical conductivity of 5000 S/cm in the upper-UV region, while reflectivity remains below 30 % in the energy range of 0–12 eV. The study suggests potential applications for these compounds in UV light emitters, sensors, photodetectors, and thermal producers.

The thermal equation of state of the magma Ocean

As the protolunar disk formed by the giant impact with the incoming asteroid Theia started to cool, the Earth condensed in its center as a molten planet. The outer layer, rich in lithophile oxides, formed the magma ocean, whose dynamical behavior heavily influenced the entire evolution of the early Earth. Here, we employ first-principles molecular dynamics simulations to characterize the magma ocean in its initial stage. We compute the compressibility and the viscosity of the molten pyrolite, which best approximates the bulk silicate Earth composition. With an extensive set of calculations, we span the entire relevant pressure-temperature range. We provide a detailed analysis of the athermal and thermal equations of state in various formulations. We obtain a linear temperature dependence for the bulk modulus using the 4th order Birch-Murnaghan equation of state. We show that the liquid silicate accommodates compression by the collapse of the second Si-O coordination sphere, whose corresponding coordination number passes from about 24 at the surface of the magma ocean to about 40 at its deepest point. We found that pyrolite melts have a very low viscosity, about one order of magnitude lower than that of molten basalt. We also propose a revised position of the critical point of the bulk silicate Earth, which lies around 6000 K and 1.1–1.2 kbars.

First principles study of thermo-physical and opto-electronic properties of NaCuTe, NaCuSe and NaScSn as potential photovoltaics

In this comprehensive study, we delved into the electronic, structural, elastic, optical and thermodynamic properties of sodium-based ternary semiconductors i.e NaCuTe, NaCuSe and NaScSn. Employing first-principle calculations, we precisely determined various material properties. The lattice constants, bulk modulus and equilibrium total energies were derived using the Murnaghan equation of state and demonstrate a good agreement with other theoretical methods. Analysis of the absorption spectra allowed us to identify the active window of the electromagnetic spectrum for these materials. The determination of elastic constants provided crucial insights into the materials’ ability to withstand external stress, revealing that the materials meet stability criteria with a ductile behavior. Electronic band structures and density of states calculations unveiled band gaps of 1.40 eV, 1.03 eV and 1.15 eV for NaCuTe, NaCuSe and NaScSn, respectively. This suggests their suitability for photovoltaic applications. Additionally, the materials exhibited desirable optical properties, characterized by efficient optical absorption with the highest peaks in the visible light and ultraviolet region of the electromagnetic spectrum, low reflectivity and a high dielectric constant. These findings collectively indicate the materials’ potential for utilization as solar photovoltaics

A comprehensive DFT insight on physical features regarding potential applicability of double perovskites K2YCuZ6 (Z = Cl, Br) for energy harvesting applications

Herein, a comprehensive investigation of the structural, mechanical, optoelectronic, and thermoelectric features of K2YCuZ6 (Z = Cl, Br) is presented concerning their potential utilization inphotovoltaic and thermoelectric devices. The observation of formation energy and fitting of the Murnaghan equation of state ensured thermodynamic and structural stability, respectively. The mechanical stability of K2YCuCl6 and K2YCuBr6 is determined by employing Born Huang stability criteria based on their elastic constants. The analysis of elastic parameters further classified these materials as anisotropic as well as ductile. The band gaps of K2YCuCl6 and K2YCuBr6 have been computed using the TB-mBJ potential, resulting in values of 2.4 and 1.56 eV, respectively. An extensive analysis of the optical characteristics of these compounds is carried out in the energy region spanning from 0 to 8 eV. These compounds are discovered to have substantial absorbance and conductive properties in the visible and ultraviolet energy ranges. On the other hand, they exhibit transparency to incoming photons with lower energy levels. Our examination of the optical characteristics indicates that these compounds are very suitable for use in photovoltaic applications. The evaluation of thermoelectric parameters resulted in the p-type semiconducting nature and higher figure of merit of 0.78, and 0.80 at 300 K. Therefore, K2YCuZ6 that has not been verified experimentally has great potential for solar cell and thermoelectric applications, indicating its ability to contribute to the progress of alternative energy sources.