Binding energies are traditionally simulated using cluster models by computation of each synthon for each individual co-crystal former. However, our investigation of the binding strengths using the electron localization function (ELF) reveals that these can be determined directly from the crystal supercell computations. We propose a new modeling protocol for the computation of physical binding energies directly from bulk simulations using ELF analysis. In this work, we establish a correlation between ELF values and binding energies calculated for co-crystals of 4-hydroxyphenylboronic acid (4HPBA) with four different aza donors using density functional theory with varying descriptions of dispersion. Boronic acids are gaining significant interest in the field of crystal engineering, but theoretical studies on their use in materials are still very limited. Here, we present a systematic investigation of the non-covalent interactions in experimentally realized co-crystals. Prior diffraction studies on these complexes have shown the competitive nature between the boronic acid functional group and the para-substituted phenolic group forming heteromeric interactions with aza donors. We determine the stability of the co-crystals by simulating their lattice energies, and the different dispersion descriptions show similar trends in lattice energies and lattice parameters. Our study bolsters the experimental observation of the boronic acid group as a competitive co-crystal former in addition to the well-studied phenolic group. Further research on correlating ELF values for physical binding could potentially transform this approach to a viable alternative for the computation of binding energies.

Anti-perovskites A₃SnO (A = Ca, Sr, and Ba) are an important class of materials due to the emergence of Dirac cones and tiny mass gaps in their band structures originating from an intricate interplay of crystal symmetry, spin-orbit coupling, and band overlap. This provides an exciting playground for modulating their electronic properties in the two-dimensional (2D) limit. Herein, we employ first-principles density functional theory (DFT) calculations by combining dispersion-corrected SCAN + rVV10 and mBJ functionals for a comprehensive side-by-side comparison of the structural, thermodynamic, dynamical, mechanical, electronic, and thermoelectric properties of bulk and monolayer (one unit cell thick) A₃SnO anti-perovskites. Our results show that 2D monolayers derived from bulk A₃SnO anti-perovskites are structurally and energetically stable. Moreover, Rashba-type splitting in the electronic structure of Ca₃SnO and Sr₃SnO monolayers is observed owing to strong spin-orbit coupling and inversion asymmetry. On the other hand, monolayer Ba₃SnO exhibits Dirac cone at the high-symmetry Γ point due to the domination of band overlap. Based on the predicted electronic transport properties, it is shown that inversion asymmetry plays an essential character such that the monolayers Ca₃SnO and Sr₃SnO outperform thermoelectric performance of their bulk counterparts.

Real-time monitoring of sugar molecules is crucial for diagnosis, controlling, and preventing diabetes. Here, we have proposed the potential of porous C₂N monolayer-based glucose sensor to detect the sugar molecules (glucose, fructose, and xylose) by employing the van der Waals interactions corrected first-principles density functional theory and non-equilibrium Green’s function methods. The binding energy turns out to be -0.93 (-1.31) eV for glucose, -0.84 (-1.23) eV for fructose, and -0.81 (-1.30) eV for xylose in gas phase (aqueous medium). The Bader charge analysis reveals that the C₂N monolayer donates charge to the sugar molecules. The dimensionless electron localization function highlights that glucose, fructose, and xylose bind through physisorption. The adsorption of sugar molecules on the C₂N monolayer increases the workfunction compared to 3.54 eV (pristine C₂N) with about 2.00 eV, indicating a suppressed probability of electron mobility. The electronic transport properties of C₂N based device reveals distinct characteristics and zero-bias transmissions. The distinctive properties of the C₂N monolayer can be indexed as promising identifiers for glucose sensors to detect blood sugar.

Intense research has been done to build materials that are potential candidates for energy storage applications. Spinels are of great interest in this respect because they have vast potential to be used in Mg-based batteries. To explore their energy storage as well as transport response, we calculate Mg-based spinels, namely MgLu₂Z₄ (ZS, Se). The full potential linearized augmented plane wave method has been used to examine their optoelectronic and transport response. An increase in the lattice constant has been observed by replacing S with Se, and our calculated values are in good agreement with those obtained experimentally. The Tran-Blaha modified Becke-Johnson exchange potential (TB-mBJ), has been used to study the optoelectronic and thermoelectric characteristics of the respective spinels. The dependence of these properties on the bandgap has also been observed. Replacing S with Se resulted in the transformation of the electronic bandgap from near-infrared to the visible region (MgLu₂S₄: 2.60 eV and MgLu₂Se₄: 2.00 eV). These results showed that these materials have the potential to be used in optoelectronic devices. The optical properties are discussed as a function of energy. Besides, the thermal transports are discussed with the help of Seebeck coefficient and figure of merit as a function of chemical potential and temperature.

We have combined first-principles and semiclassical Boltzmann transport theory to demonstrate the potential superb electronic and thermal transport properties of bulk and monolayer bismuth oxyiodide (BiOI). The exfoliation energy required to produce monolayer BiOI (22.53 meV/angstrom (2)) is lower than that required to produce monolayer h-BN, implying possible manufacturing from bulk. The calculated phonon frequencies, complemented with an ab initio molecular dynamic simulation for 8 ps at elevated temperature (900 K), reveal the monolayer’s dynamic and structural stability. The calculated band gaps are indirect for both bulk and monolayer and amount to 2.04 eV and 2.07 eV, respectively. Our results indicate remarkably high Seebeck coefficients for BiOI in the bulk (227 mu V/K at a hole concentration of 9.00 x 10(20) cm(-3)) and in the monolayer form (200 mu V/K at a hole concentration of 8.14 x 10(13) cm(-2)) at 900 K. The lowest lattice thermal conductivities of 1.35 W/mK for the bulk and 1.44 W/mK for the monolayer are obtained at 900 K. Because of the high value of S-2 sigma/tau for p-type doping, the figure of merit achieves peak values of 1.51 at a carrier concentration of 8.44 x 10(20) cm(-3) for bulk BiOI and 1.61 at a carrier concentration of 4.27 x 10(13) cm(-2) for monolayer BiOI.

By using WIEN2k code, we investigated the mechanical and thermoelectric properties of magnesium based MgX2O4 (X = Rh and Bi) spinels. To compute the mechanical behavior of MgX2O4 (X = Rh and Bi), the Perdew-Bruke-Ernzerhof (PBEsol) flavor of generalized gradient approximation is used. From structural optimization, ground state lattice constant (a0) show a comparable with the previously evaluated theoretical and experimental values. The Born stability criterion represents that the investigated spinels are stable in the cubic phase and their ductile behaviors are observed by calculating Pugh’s ratio as well as Poisson ratio. Besides, thermodynamic behavior is concluded in terms of the Debye temperature. To investigate the electronic and thermoelectric behavior, the modified Becke and Johnson (mBJ) potential is employed. Finally, we investigated the thermoelectric behavior to represent the importance of studied spinels in thermoelectric appliances by calculating the figure of merit (ZT). High values of the See-beck coefficient and ZT at room temperature explores the potential of the studied spinels in thermoelectric devices.

The phonon transport properties of CuSCN and CuSeCN have been investigated using the density functional theory and semiclassical Boltzmann transport theory. The Perdew–Burke–Ernzerhof functional shows an indirect (direct) electronic band gap of 2.18 eV (1.80 eV) for CuSCN (CuSeCN). The calculated phonon band structure shows that both compounds are dynamically stable. The Debye temperature of the acoustic phonons is 122 and 107 K for CuSCN and CuSeCN, respectively. The extended in-plane bond lengths as compared to the out-of-plane bond lengths result in phonon softening and hence, low lattice thermal conductivity. The calculated room temperature in-plane (out-of-plane) lattice thermal conductivity of CuSCN and CuSeCN is 2.39 W/mK (4.51 W/mK) and 1.70 W/mK (3.83 W/mK), respectively. The high phonon scattering rates in CuSeCN give rise to in-plane low lattice thermal conductivities. The room-temperature Grüneisen parameters of CuSCN and CuSeCN are found to be 0.98 and 1.08, respectively.

A comprehensive investigation of the physical characteristics of any material provides beneficial information regarding its application viewpoint in different industries. Herein, we report the tunable mechanical and optoelectronic properties of cubic CdZrO₃ under variable pressure up to 80 GPa using density functional theory (DFT). The pressure-induced band gap engineering reveals a fantastic fact of transformation of the indirect to direct band gap with increasing pressure. The dielectric response disclosed that optical parameters dragged towards higher energy with an increase of pressure, which unveiled the potential of CdZrO₃ for optoelectronic applications. Effective change in optoelectronic is attributed to indirect to direct band gap transition. This study provides a gateway to how the optoelectronic properties of cubic CdZrO₃ could be tuned by employing external pressure.

Recently, the bismuth oxybromide quintuple-layer (QL) was experimentally realized. In the present study, we extensively examine the stability, electronic and thermal transport of bulk bismuth oxybromide (BiOBr) and QL based on first-principles calculations and the semiclassical Boltzmann transport theory. We have found that the bulk and QL BiOBr systems are dynamically and thermally stable with an indirect band gap of 2.86 and 3.08 eV, respectively. The emergence of comparatively flat bands at the top valence band favours the pronounced p-type Seebeck coefficient. Our calculated results demonstrate a high Seebeck coefficient of 1569.82 μV/K and 1580 μV/K for bulk and QL BiOBr materials at high temperatures. At higher temperature, the lattice thermal conductivity values of bulk are 1.32/0.23 for in-plane/out-of-plane, respectively and 1.85 W/mK in QL BiOBr, which are relatively low compared to other layered materials, e.g., MX2 (M = Mo, W, Pt, Zr, and X  = S, Se, Te). The figure of merit (ZT) turns out to be as high as 3.52 for bulk BiOBr and 1.5 for QL BiOBr at higher temperatures,suggest them as good candidates for thermoelectric applications.

Gas-sensing properties of nitrogenated holey graphene (C2N), graphdiyne (GDY) and their van der Waals heterostructure (C2N…GDY) have been studied towards particular volatile organic compounds (VOCs) by means of spin-polarized, dispersion-corrected DFT calculations. We find that VOCs such as acetone, ethanol, propanal, and toluene interact weakly with the GDY monolayer; however, the bindings are significantly enhanced with the C2N monolayer and the hybrid C2N…GDY heterostructure in AB stacking. Electron localization function (ELF) analysis shows that all VOCs are van der Waals bound (physical binding) to the 2D materials, which result in significant changes of the charge density of C2N and GDY monolayers and the C2N…GDY heterostructure. These changes alter the electronic properties of C2N and GDY, and the C2N…GDY heterostructure, upon VOC adsorption, which are investigated by density-of-states plots. We further apply thermodynamic analysis to study the sensing characteristics of VOCs under varied conditions of pressure and temperature. Our findings clearly indicate that the C2N…GDY heterostructure is a promising material for sensing of certain VOCs.