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S. H. Naqib

Publications and source records attributed to S. H. Naqib.

At least 19 recordsLinked to original sources
arXiv2026

Nitrogen based electride superconductor Nb5Ir3N under pressure: multifunctional physical properties from DFT based first-principles investigation

Discovery and study of superconducting electrides have opened new avenues in condensed matter physics, driven by their intriguing multifunctional features spanning ambient and high-pressure regimes. This work investigates the ternary nitride superconductor Nb5Ir3N under pressure ranging from 0 to 20 GPa via density functional theory based simulations. Estimated structural parameters agree well with the available data, confirming their reliability and supporting the validity of this analysis. Negative formation enthalpy, together with evaluated elastic constants and phonon spectra, confirm the structural, thermodynamic, mechanical, and dynamical stability of Nb5Ir3N over the entire pressure range. Pressure dependent elastic constants and polycrystalline elastic moduli are investigated. The compound is categorized as ductile in light of estimated mechanical indices. Elastic anisotropy factors indicate that Nb5Ir3N remains anisotropic, with the degree of anisotropy gradually decreasing as pressure increases. Electronic band structure and density of states are calculated with and without spin orbit coupling to investigate its influence on the electronic structure. Calculated optical response reveals substantial intraband contributions in the low energy region, intense ultraviolet absorption, and strong reflectivity. The spectra exhibit optical anisotropy and a broadening at higher pressures. Pressure induced superconducting features are also discussed qualitatively.

cond-mat.mtrl-sci↗
arXiv2026

Electronic Structure, Optical Response, Thermal and Mechanical Behavior of B6X (X = S, Se) under Pressure: A Comprehensive Ab-initio Exploration

This study presents a comprehensive investigation of the pressure dependent structural, electronic, optical, mechanical, and bonding properties of orthorhombic boron rich chalcogenides B6S and B6Se. Calculations were performed using density functional theory across a wide range of hydrostatic pressures. The computed elastic constants, bulk, Young, shear moduli, and Poisson ratio, revealed mechanical robustness and strong resistance to deformation, even under significant compression. Electronic band structure and density of states analyses indicate that the materials exhibit indirect bandgap semiconducting behavior. Optical results reveal clear pressure induced spectral shifts, particularly in the visible and ultraviolet regions, suggesting modified light matter interaction under compression. Phonon dispersion curves verified the dynamical stability of both materials within the investigated pressure range. Hardness estimations, combined with elastic parameters, and melting temperatures, further indicate that B6S and B6Se possess significant mechanical strength suitable for applications under harsh environments. The thermal properties suggest that both these compounds possess features suitable to be used as excellent thermal barrier coating materials.

cond-mat.mtrl-sci↗
arXiv2026

First-Principles Study of Novel Lead-Free Double Perovskite \b{eta}2SnGeX6 (\b{eta} = K, Rb; X = Cl, Br, I) for thermomechanical, optoelectronic and outstanding thermoelectric applications

In this study, the structural, mechanical, electronic, optical, and thermoelectric properties of the novel lead-free halide double perovskite series beta2SnGeX6 (beta = K, Rb; X = Cl, Br, I) are systematically investigated using density functional theory (DFT). Calculated formation energies, Tolerance factors, and octahedral factors confirm that all six compounds exhibit robust thermodynamic stability within a highly symmetric cubic geometry. Mechanical analysis derived from elastic parameters characterizes the entire series as fundamentally ductile, ensuring high processing elasticity and resistance to micro-cracking during device manufacturing. Electronic band structures reveal direct bandgaps showing exceptional composition-dependent tunability from 1.44 eV down to 0.64 eV via progressive halogen substitution. The wide gap chloride variations are optimized for single-junction photovoltaic absorbers, while the narrower-gap bromide and iodide analogs show immense promise for tandem solar architectures and near-infrared photodetectors. Thermoelectrically, heavy constituent atoms introduce strong lattice anharmonicity and intense high-temperature Umklapp phonon scattering, significantly suppressing lattice thermal conductivity. Combined with low carrier effective masses that optimize electrical transport, the iodide compounds achieve higher power factors and outstanding dimensionless figures of merit (ZT = 2.4 for K2SnGeI6 at 1000 K). Ultimately, these lead-free double perovskite family emerges as an environmentally benign and versatile platform for next-generation green optoelectronics and solid-state waste-heat recovery.

cond-mat.mtrl-sci↗
arXiv2026

Exploring the Physical Properties, Hydrogen Storage Capacity and Thermal Barrier Performance of LaMg2H7: A First-Principles Investigation

LaMg2H7 is a ternary wide band gap semiconductor that is a member of the hydride family. The bulk physical characteristics of the LaMg2H7 compound, including its structural, electronic band structure, elastic, thermal, and optical characteristics, have been examined in this work utilizing density functional theory (DFT). The elastic constants indicate that {\rm LaMg}_2H_7 is mechanically stable, brittle in nature, and anisotropic. This studied compound possesses a moderate level of hardness. The band structure and density of states have been examined to have a better understanding of its electronic behavior. The intrinsic carrier concentrations and effective masses have been determined using the band structure. The gravimetric hydrogen storage capacity (Cwt%) has been calculated, indicating that this compound is suitable for hydrogen storage applications. This compound is dynamically stable, as confirmed by its phonon dispersion. Here, the details of this wide-band-gap semiconductor's reflectivity, absorption coefficient, refractive index, dielectric function, optical conductivity, and loss function are investigated. The substance is a moderate reflector of ultraviolet (UV) light. The absorption and conductivity support the gap in the band structure. The thermodynamic properties, such as bulk modulus, internal energy, specific heat capacity, entropy, thermal expansion coefficient, and Debye temperature, have been explored at varying temperatures and pressures. {\rm LaMg}_2H_7 has a moderate level of melting temperature with higher lattice thermal conductivity. The value of the thermal expansion coefficient and minimum thermal conductivity is highly recommended for use as a thermal barrier coating (TBC).

cond-mat.mtrl-sci↗
arXiv2026

Physical properties of transition metal hydride superconductors Mg2TmH6 (Tm = Rh, Pd, Ir, Pt) by first-principles calculations

In this work, a comprehensive first-principles investigation of the structural, hydrogen storage potential, electronic, elastic, mechanical, thermophysical, superconducting, and optical properties of Mg2TmH6 (Tm = Rh, Pd, Ir, Pt) hydrides is presented. Obtained results demonstrate that Mg2TmH6 hydrides combine favorable hydrogen storage, mechanical robustness, superconductivity, and multifunctional optical properties, making them promising candidates for energy storage, superconducting and advanced optoelectronic applications.

cond-mat.mtrl-sci↗
arXiv2025

Ab-initio Study of Structural, Magnetic, Optoelectronic and Thermo-Physical Properties of HoPdBi Half-Heusler Semimetal

In this investigation, we have used the density functional theory (DFT) to investigate several aspects of the half-Heusler compound HoPdBi. The following properties have been studied: spin polarized electronic properties, magnetic moment, phonon dispersion with phonon density of states, structural, elastic properties, optical characteristics, and thermo-physical features. The calculated unit cell volume and ground-state lattice characteristics closely match the experimental results. This study is the first to examine the optoelectronic, thermo-physical, and elastic characteristics of HoPdBi. The mechanical stability requirements were met by the calculated elastic constants. The compound's ductility is shown by the estimated Pugh's ratio, Poisson's ratio, and Cauchy pressure. Band structures and electronic energy density of states have been evaluated in order to better understand the magnetic features with spin polarization. Band structure simulations were conducted with and without the spin-orbit coupling (SOC) effect in order to look into any topological signature. The electrical band structure of the compound shows semi-metallic properties. The reflectivity, absorption coefficient, refractive index, dielectric function, optical conductivity, and loss function of this semi-metal have all been thoroughly examined. The compound is a good reflector in infrared region and a good absorber of ultraviolet (UV) light. This compound is a suitable candidate for high temperature applications and possesses potential as heat sink because of its high melting point and thermal conductivity. It is also suitable for spintronics applications. The majority of this study's findings are completely novel.

cond-mat.mtrl-sci↗
arXiv2025

DFT based comparative study of the physical properties of MAlB (M = V, Ta, Mo, Nb) MAB compounds

MAB phases have appealing physical features that make them appropriate for a wide range of applications. Motivated by this, we present density functional theory (DFT) calculations of the structural, elastic, bonding, electronic band dispersion, acoustic behavior, phonon spectrum, various thermomechanical and optoelectronic properties of VAlB and TaAlB ternary borides for the first time. The computed ground state lattice parameters of both compounds are very consistent with experimental data. The formation enthalpy, elastic constants, and phonon dispersion calculations indicate that both compounds are chemically, mechanically, and dynamically stable, respectively. The physical parameters of VAlB and TaAlB are studied and compared with those of MoAlB and NbAlB MAB compounds.

cond-mat.mtrl-sci↗
arXiv2025

DFT exploration of pressure dependent physical properties of the recently discovered La3Ni2O7 superconductor

The recent discovery of superconductivity in Ruddlesden-Popper bilayer nickelate La3Ni2O7 under pressure has drawn a lot of interest. La3Ni2O7 is isostructural with cuprates in some respect. Investigation of its properties will undoubtedly provide new insights into high-Tc superconductivity. In the present work, we study structural, mechanical, elastic, optoelectronic, thermophysical properties, and Fermi surface topology of La3Ni2O7 under pressure within the range of 30-40 GPa employing the density functional theory (DFT). The calculated structural parameters agree well with the earlier experimental findings. The structural, mechanical, and thermodynamical stability is justified across the entire pressure range. The computed elastic moduli classify the compound as ductile, and the material's ductility is largely unaffected by pressure. The compound has a high level of machinability index and dry lubricity. The electronic band structure reveals metallic feature of La3Ni2O7. The Debye temperature, thermal conductivity, and melting temperature increase with increasing pressure, but in an anomalous manner. The characteristic peaks in refractive index, reflectivity, and photoconductivity exhibit a small shift towards higher energy for all polarizations of the electric field vector with increasing pressure. The investigated material might be a good ultraviolet radiation absorber and can be used as an anti-reflection system. Moreover, the pressure dependent electronic density of states at the Fermi level, pressure induced negligible variations in the repulsive Coulomb pseudopotential, and the changes in the Debye temperature have been used to explore the effect of pressure on the superconducting transition temperature in this study.

cond-mat.supr-con↗
arXiv2025

DFT based insights into elastic, thermophysical, electronic and optical properties of topological insulators XTe5 (X = Zr, Hf)

Transition metal penta-tellurides, ZrTe5 and HfTe5 have been recently drawn a lot of attention due to their fascinating physical properties and for being prominent materials showing topological phase transitions. In this study, we investigated mechanical, thermophysical and optoelectronic properties of these materials which remained almost unexplored till now. We also studied electronic properties and compared those with previous studies. We used Density Functional Theory (DFT) based calculations to study all of these properties. This study suggests that the materials are mechanically stable, possess high mechanical and bonding anisotropy and are brittle in nature. Our study also suggests that the compounds are soft in nature and they contain a mixture of covalent and metallic bonding. Investigation of thermophysical properties, namely, Grüneisen parameter and Debye temperature indicates weak bonding strength in these compounds. Analysis of melting temperature, thermal expansion coefficient, heat capacity, radiation factor, acoustic impedance, and minimum thermal conductivity suggests their possible application in acoustic and thermoelectric devices. Examination of their optical characteristics reveals that they have a considerable reflectivity from the infrared to the ultraviolet region. The refractive indices of these materials are high at low energy so they are potential candidates for reflective coating of solar radiation. There have been debates over exact topological natures of these compounds, whether they are semi-metals or insulators. Our study of electronic band structure and density of states reveal that spin-orbit interaction is responsible for enhancing energy gaps and promoting insulating characteristics in these compounds.

cond-mat.mtrl-sci↗
arXiv2025

Pressure dependent ab initio study of the physical properties of hexagonal BeB2C: a possible high-Tc superconductor

This study uses the Density Functional Theory to explore the pressure dependent properties of hexagonal BeB2C. The metallic nature of BeB2C was substantiated at ambient pressure, with pressure induced alterations in electronic band structure and Fermi surface topology suggesting a potential for tunability across various applications. The phonon dispersion and phonon density of states show the dynamical stability under pressure. The thermophysical properties are also investigated under varying pressure conditions. Finally, the exploration of superconducting properties found that the transition temperature is in good agreement with previously reported values, and illustrated that beB2C holds considerable promise as a high-temperature superconductor, with pressure augmenting its superconducting properties.

cond-mat.mtrl-sci↗
arXiv2024

DFT based comparative analysis of physical properties of binary metallic diborides XB$_2$ (X = Cr, Mo and W)

Transition-metal borides (TMBs) have long attracted attention of the researchers because of their unique mechanical and electrical properties including superconductivity. We have explored the structural, mechanical, electronic, optical, and some thermophysical properties of XB$_2$ (X = Cr, Mo and W) binary metallic diborides in detail employing density functional theory based first-principles method. Many of the physical properties, including direction-dependent mechanical properties, optical properties, and thermo-mechanical properties are being investigated for the first time.

cond-mat.mtrl-sci↗
arXiv2024

DFT exploration of novel direct band gap semiconducting halide double perovskites, A2AgIrCl6 (A = Cs, Rb, K), for solar cells application

Double perovskite halides are promising materials for renewable energy production, meeting the criteria to address energy scarcity issues. As a result, studying these halides could be useful for optoelectronic and solar cell applications. In this study, we investigated the structural, mechanical, thermodynamic, electronic, and optical properties of A2AgIrCl6 (A = Cs, Rb, K) double perovskite halides using density functional theory calculations with the full-potential linearized augmented plane-wave (FP-LAPW) approach, aiming to evaluate their suitability for renewable energy devices. The Goldsmith tolerance factor, octahedral factor, and new tolerance factor have confirmed the cubic stability of the predicted compounds. We have also verified the thermodynamic stability of these compounds by calculating the formation enthalpy, binding energy, and phonon dispersion curves. Additionally, Born-Huang stability requirements on stiffness constants confirmed the mechanical stability of the titled compounds. To predict the accurate optoelectronic properties, we employed the TB-mBJ potential. The electronic band structure calculations revealed that the titled halides exhibit a direct band gap semiconducting nature with values of 1.43 eV, 1.50 eV, and 1.55 eV for Cs2AgIrCl6, Rb2AgIrCl6, and K2AgIrCl6, respectively. Besides, all these compounds showed remarkably low effective electron masses, indicating their potential for high carrier mobility. Furthermore, the optical properties of A2AgIrCl6 (A = Cs, Rb, K) compounds demonstrated very low reflectivity and excellent light absorption coefficients (105 cm-1) in the visible light spectrum, suggesting their suitability as an absorbing layer in solar cells. The photoconductivity and absorption spectra of these compounds validate the accuracy of our band structure results.

cond-mat.mtrl-sci↗
arXiv2024

First-principles exploration of the pressure dependent physical properties of Sn4Au: a superconducting topological semimetal

First-principles investigation within the density functional theory is utilized to explore the physical properties of a superconducting topological semimetal Sn4Au under pressure within the range of 0-5 GPa. According to the computed elastic moduli, the compound under study is classified as ductile and applied pressure enhances the ductility. The compound has very high level of dry lubricity and machinability index. All the anisotropy factors demonstrate an elastically anisotropic nature. The electronic properties are investigated in view of the electronic band structure and density of states. The band structure reveals the topological semimetallic feature of Sn4Au while the density of states at the Fermi level decreases gradually with increasing pressure. Both ionic and covalent bondings are observed in Sn4Au. Optical parameters of Sn4Au are investigated at different pressures. The characteristic peaks in reflectivity, refractive index and photoconductivity exhibit a shift towards higher energy with increasing pressure for all polarizations of the electric field vector. The absorption coefficient and reflectivity spectra designate Sn4Au as a suitable system for optoelectronic applications. Moreover, the pressure dependent shifts in the electronic density of states at the Fermi level, the changes in the Debye temperature, and pressure induced variations in the repulsive Coulomb pseudopotential have been used to explore the effect of pressure on the superconducting transition temperature in this study.

cond-mat.mtrl-sci↗
arXiv2024

First-principles investigation of the physical properties of wide band gap hexagonal AlPO4 compound for possible applications

In this study, using the density functional theory, we have investigated the bulk physical properties like structural, electronic band structure, elastic properties, thermal properties, optical properties and bonding features of AlPO4 compound in the hexagonal form. The values of our optimized structural parameters are very close to the previous results. Most of the results presented in this work are novel. The elastic constants indicate that AlPO4 is mechanically stable and brittle in nature. The compound is moderately hard and possesses low machinability index. AlPO4 contains significant elastic anisotropy. The charge density distribution , bond population analysis, Vickers hardness, thermo-mechanical properties, and optical properties have been investigated for the first time. The electronic band structure calculations reveal clear insulating behavior with a band gap of 6.0 eV. Band structure calculations were carried out without and with spin-orbit coupling (SOC) to explore possible topological signature. The energy dependent optical properties conform to the electronic band structure calculations. Major optical properties like dielectric functions, refractive index, photoconductivity, absorption coefficient, loss function and reflectivity are calculated and discussed in detail in this study. The compound is optically anisotropic. It is an efficient absorber and reflector of the ultraviolet light.

cond-mat.mtrl-sci↗
arXiv2024

A detailed first-principles study of the structural, elastic, thermomechanical and optoelectronic properties of binary rare-earth tritelluride NdTe3

Rare-earth tritellurides (RTe3) are popular for their charge density wave (CDW) phase, magnetotransport properties and pressure induced superconducting state among other features. In this literature, Density functional theory has been exploited to study various properties of NdTe3. The calculated elastic and thermomechanical parameters, which were hitherto untouched for any RTe3, uncover soft, ductile, highly machinable and damage tolerant characteristics, as well as highly anisotropic mechanical behavior of this layered compound. Its thermomechanical properties make it a prospective thermal barrier coating material. Band structure, density of states, Fermi surfaces and various optical functions of the material have been reported. The band structure demonstrates highly directional metallic nature. The highly dispersive bands indicate very low effective charge carrier mass for the in-plane directions. The Fermi surfaces display symmetric pockets, including signs of nesting, bilayer splitting among others, corroborating previous works. The optical spectra expose high reflectivity across the visible region, while absorption is high in the ultraviolet region. Two plasma frequencies are noticed in the optical loss function. The optical conductivity, reflectivity and absorption reaffirm its metallic properties. The electronic band structure manifests evidence of CDW phase in the ground state.

cond-mat.mtrl-sci↗
arXiv2024

Ab-initio insights into the mechanical, phonon, bonding, electronic, optical and thermal properties of hexagonal W2N3 for potential applications

We investigated the structural, elastic, electronic, vibrational, optical, thermodynamic and a number of thermophysical properties of W2N3 in this study using DFT based formalisms. The mechanical and dynamical stabilities have been confirmed. The Pugh and Poisson ratios are located quite close to the brittle to ductile borderline. The electronic band structure and energy density of states show metallic behavior. The Fermi surface features are investigated. The analysis of charge density distribution map clearly shows that W atoms have comparatively high electron density around than the N atoms. Presence of covalent bondings are anticipated. High melting temperature and high phonon thermal conductivity at room temperature of W2N3 imply that the compound has potential to be used as a heat sink system. The optical characteristics demonstrate anisotropy for W2N3. The compound can be used in optoelectronic device applications due to its high absorption coefficient and low reflectivity in the visible to ultraviolet spectrum. Furthermore, the quasiharmonic Debye model is used to examine temperature and pressure dependent thermal characteristics for the first time.

cond-mat.mtrl-sci↗