Negative Enthalpy Research Articles

Preparation of High-Entropy (Zr0.25Hf0.25Ta0.25Ti0.25)C-Ni-Co Composite by Spark Plasma Sintering

In the present work, the thermodynamic formation possibility and stability of high-entropy (Zr0.25Hf0.25Ta0.25Ti0.25)C ceramic single phase were theoretically calculated by first principles, and a novel (Zr0.25Hf0.25Ta0.25Ti0.25)C high-entropy ceramic-Ni-Co composite was successfully prepared by spark plasma sintering (SPS). The first principles calculation indicated the atomic size difference δ for (Zr0.25Hf0.25Ta0.25Ti0.25)C was 3.23 pct, which was < 6.6 pct, and solid solution would possibly happen. The calculated DFT formation enthalpy of the (Zr0.25Hf0.25Ta0.25Ti0.25)C system was − 1.78 eV. The negative formation enthalpy indicated that (Zr0.25Hf0.25Ta0.25Ti0.25)C was thermodynamically stable. The experimental results showed a new fcc (Fm-3m) single rock salt crystal structure ceramic phase was formed after SPS sintering. Two phases (ceramic phase and metal phase) were presented in the material. Besides, for the (Zr0.25Hf0.25Ta0.25Ti0.25)C phase, the Hf, Ta, Zr and Ti distributed uniformly, and no secondary phase was detected. The metal phase was homogeneous along the ceramic phase. No pores and gaps existed between the ceramic phase and metal phase. Good bonding was obtained, caused by some Hf, Ta, Zr or Ti atoms diffusing in the metal phase. The fracture toughness and hardness of the high-entropy (Zr0.25Hf0.25Ta0.25Ti0.25)C ceramic–metal composite were 14.2 MPa m1/2 and 1620 HV(30). The excellent comprehensive performance was caused by good bonding between the ceramic phase and metal phase and mass disorder in the (Zr0.25Hf0.25Ta0.25Ti0.25)C phase.

Protonation of Planar and Nonplanar Porphyrins: A Calorimetric and Computational Study.

Herein, we report the first calorimetric study of the protonation of planar and nonplanar free-base porphyrins: H2OETPP (strongly saddled by its substituents), H2T(tBu)P (strongly ruffled by its substituents), and the nominally planar porphyrins (npPs) H2OEP, H2TPP, H2T(nPe)P, and H2T(iPr)P. The observed enthalpies of protonation in solution (ΔHprotsoln) for formation of the dications in 1,1,2,2-tetrachloroethane with 2% trifluoroacetic acid are -45 ± 1 kcal mol-1 for the npPs, -52.0 kcal mol-1 for H2T(tBu)P, and -70.9 kcal mol-1 for H2OETPP. The corresponding enthalpies of protonation (ΔHDFT) obtained from DFT calculations (-27 ± 5, -42, and -63 kcal mol-1, respectively) reproduce this trend. The much more negative enthalpy of protonation seen for H2OETPP is consistent with this molecule being pre-deformed into the saddle structure favored by porphyrin dications. Except for OETPP, the calculated enthalpies of the first protonations (ΔH1) are significantly more positive than the enthalpies of the second protonations (ΔH2). In addition, the structural strain energies for the first protonations (ΔEst(1)) are also significantly more positive than ΔEst(2). According to the calculations, the monocations thus have higher proton affinities than the corresponding free-base porphyrins due to a structural strain effect, which is consistent with the generally elusive nature of the porphyrin monocation. The recent observations of monocations for free-base porphyrins with a high degree of saddling can be rationalized in terms of ΔH1 and ΔH2 being similar; so, the monocation is no longer an unstable intermediate.

A comparison study of C19T (T = C, Cr, Ti, Fe, and Ni) nanocages by first-principle DFT calculation for removal of ozone-destroyer pollutants.

In the present work, the interaction of dichloromethane (CH2Cl2) and chloroform (CHCl3) on C20 and C19T (T = Cr, Ti, Fe, Ni) has been studied by density functional theory (DFT). The results have been investigated by binding energy, net charge transfer, electrical and thermodynamic properties, and frontier orbitals. Although the complexes of CH2Cl2 and CHCl3 on free C20 nanocages showed slightly binding energy (- 0.029 and - 0.006eV, respectively), doping of Cr, Ti, Fe, Ni transition metal atoms on C20 nanocage improved the binding energy. The best binding energy was attributed to the adsorption of CH2Cl2 on C19Cr (- 0.755eV). Based on ESP maps, doping of Cr, Ti, Fe, and Ni is the cause of strong electrophilic region creation which is very useful for adsorption process CH2Cl2 and CHCl3 on nanocages. Also, natural bond orbital (NBO) analysis showed that the best charge transfer was 0.253eV which was related to the formation of C19Fe-CHCl3 complex. In addition, the least HOMO-LUMO energy gap between free nanocages (C20, C19Cr, C19Ti, C19Fe, and C19Ni) is 4.05eV (C19Ti). The thermodynamic investigations indicated that due to the negative enthalpy, all of the studied adsorption processes were exothermic.

The Influence of Ionic Liquids on Micellization of Sodium Dodecyl Sulfate in Aqueous Solutions

The micellization of sodium dodecyl sulfate (SDS) in water and aqueous solutions of NaCl (0.1 M) and three ionic liquids (IL, 0.01 M) with different side-chain length, i.e. 1,3-dimethylimidazolium chloride, 1-ethyl-3-methylimidazolium chloride, and 1-butyl-3-methylimidazolium chloride was investigated in the temperature range from 288.15 to 328.15 K using isothermal titration calorimetry (ITC). Thermodynamics of micellization was studied by the fitting of the mass-action model to the ITC data. The micellization of SDS in all the studied systems is an entropy-driven at lower temperatures and an enthalpy-driven at higher temperatures. It was also found that with the increasing nonpolar character of IL the interactions between the SDS should be stronger leading to more negative Gibbs free energy and enthalpy of micellization. To obtain information about the micellar charge, the conductivity and zeta-potential measurements were performed at 298.15 K. It is assumed that the charge screening between negative sulfate heads is more efficient in the presence of ILs due to their possible incorporation into the micellar structure reflecting in less negative zeta-potential of micelles comparing to SDS in water and consequently higher degrees of micelle ionization due to the larger portion of sodium ions in solution.

Effects of Doped Elements (Si, Cr, W and Nb) on the Stability, Mechanical Properties and Electronic Structures of MoAlB Phase by the First-Principles Calculation.

First-principles calculations based on density functional theory (DFT) have been performed to explore the effects of Si, Cr, W, and Nb elements on the stability, mechanical properties, and electronic structures of MoAlB ternary boride. The five crystals, with the formulas of Mo4Al4B4, Mo4Al3SiB4, Mo3CrAl4B4, Mo3WAl4B4, and Mo3NbAl4B4, have been respectively established. All the calculated crystals are thermodynamically stable, according to the negative cohesive energy and formation enthalpy. By the calculation of elastic constants, the mechanical moduli and ductility evolutions of MoAlB with elemental doping can be further estimated, with the aid of B/G and Poisson’s ratios. Si and W doping cannot only enhance the Young’s modulus of MoAlB, but also improve the ductility to some degree. Simultaneously, the elastic moduli of MoAlB are supposed to become more isotropic after Si and W addition. However, Cr and Nb doping plays a negative role in ameliorating the mechanical properties. Through the analysis of electronic structures and chemical bonding, the evolutions of chemical bondings can be disclosed with the addition of dopant. The enhancement of B-B, Al/Si-B, and Al/Si-Mo bondings takes place after Si substitution, and W addition apparently intensifies the bonding with B and Al. In this case, the strengthening of chemical bonding after Si and W doping exactly accounts for the improvement of mechanical properties of MoAlB. Additionally, Si doping can also improve the Debye temperature and melting point of the MoAlB crystal. Overall, Si element is predicted to be the optimized dopant to ameliorate the mechanical properties of MoAlB.

211-MAX borides: The stable boron-substituted 211-MAX compounds by first-principles

Applying the first-principles density functional pseudopotential plane-wave calculations, the energetic, mechanical, and dynamic stabilities of boron-substituted M2AlB (M=Sc, Ti, V, Cr, Mn, Y, Zr, Nb, Mo, Tc, Ru, Hf, Ta, W, Re, Os, Ir, Pt, Ag, and Au) compounds as the members of 211-MAX borides with Cr2AlC-type crystal structure were investigated. After well-converged geometry optimizations, the cohesive energy, formation enthalpy, single-crystal elastic constants, and phonon dispersion curves were calculated to explain the stabilities of the compounds. Except for M=Y, Ag, and Au compounds, the others are thermodynamically stable due to the negative formation enthalpies. M=Sc, Y, Zr, Hf, Os, Ir, and Pt compounds are dynamically unstable because of the negative phonon frequencies, and M=Ag and Au compounds are mechanically unstable. Beyond the detailed stability analysis, the structural, elastic, and mechanical properties, anisotropy factors, exfoliation states, and specifically hardness nature of the stable compounds were examined. A new modified hardness method, which includes the metallicity, is proposed to characterize the softness nature of MAX-phases. The relevant quantities, such as bond electronegativity, ionicity, and metallicity, were debated. The presented data were compared with available theoretical and experimental literature.

Modulation of Clouds and Rainfall by Tropical Cyclone's Cold Wakes

AbstractTropical cyclones can pump heat into the ocean by producing a long‐lasting subsurface warm anomaly while leaving a relatively short‐term surface cold anomaly via mixing the upper ocean. Although the heat pumping has been found to be crucial in driving oceanic heat transport and thereby regulating climate changes, the contribution of surface cold anomaly to the atmosphere remains unclear. Here we show that local clouds and rainfall are effectively modulated by cold wakes left behind by tropical cyclones using a combination of satellite observations. On average, the negative surface enthalpy flux anomaly associated with the cold wake results in a reduction of rainfall by ~16.6 ± 0.6% (standard error) and a decline of cloud fraction by ~6.7 ± 0.4% over the wake region. Clouds and rainfall tend to be more suppressed for slower moving or stronger TCs. With more intense or slower moving TCs in a warming climate, such a modulation could be amplified accordingly.

Study on Low-Temperature Sintering Behavior of 90W-7Ni-3Fe Alloys: The Influence of Sn Addition

In this work, we investigate low-temperature sintering behavior of the 90W-7Ni-3Fe alloy by introducing Sn. The 90W-7Ni-3Fe alloy with different Sn contents (0, 0.5, 1.0 and 1.5 wt.%) was fabricated via vacuum sintering at 1300 °C for 90 min. When 1 wt.% Sn was added, the liquidus temperature of the 90W-7Ni-3Fe alloy decreased from 1477 to 1265 °C, resulting in rapid densification (relative density increased from 77.77 to 98.59%) and an homogeneous liquid-phase sintered microstructure. Electron probe microanalysis (EPMA) and transmission electron microscopy (TEM) observations revealed that, apart from W and the γ-(Ni, Fe) phase, a new Ni3Sn2 phase appeared in the matrix phase. Furthermore, we discuss in detail the formation of the Ni3Sn2 phase based on element selection theory, which can be associated with the larger atomic radius of Sn and with the negative enthalpy of mixing Sn and Ni. Excessive Sn content (1.5 wt.%) led to the increase in Ni3Sn2 phase, and this deteriorated the relative density and tensile strength of the alloy. The 90W-7Ni-3Fe alloy with the addition of 1 wt.% Sn exhibited a maximum tensile strength value (710 MPa), which was much higher than that of the 90W-7Ni-3Fe alloy that was obtained at 1300 °C. Our findings shed light on further research directions and developed a 90W-6.3Ni-2.1Fe-1Sn alloy for low-temperature sintering.

Thermodynamic route for self-forming 1.5 nm V-Nb-Mo-Ta-W high-entropy alloy barrier layer: Roles of enthalpy and mixing entropy

This study reports a thermodynamic route for self-forming an ultrathin V-Nb-Mo-Ta-W high-entropy alloy layer for potential use as a promising diffusion barrier. In Cu alloy films minor-doped with 1.2 at.% of one-to-five metallic elements (V, Nb, Mo, Ta and W), the alloying elements spontaneously segregated. Under the competition of enthalpy and mixing entropy that determines the delta Gibbs free energy, one and, in particular, five alloying element(s) formed an alloy solution layer at the Cu/Si interface, whereas three alloying elements differently formed intermetallic compound clusters at the grain boundaries of Cu. Dominant factors for the final states of the alloying elements include the large positive enthalpy between Cu and the alloying elements, the negative enthalpy among the alloying elements, and the low-to-high mixing entropy among the alloying elements. The self-forming quinary alloy layer of only 1.5 nm thick provided excellent resistance to the interdiffusion of Cu and Si up to 700°C, better than practical and other newly developed barrier materials.

Investigation on elastic properties and electronic structure of dilute Ir-based alloys by first-principles calculations

As the potential ultrahigh temperature alloy, the brittle fracture of iridium (Ir) has puzzled people for a long time as a challenge. In this work, thirty-three alloying elements are employed to enhance the ductility of dilute Ir-based alloys by first principles calculations based on density functional theory (DFT). The results show that dilute Ir-based alloys has negative mixing enthalpy except four alloying elements (Cd, Ag, La and Au) and the four Ir-X binary alloys (X = Cd, Ag, La and Au) have positive zero-order interaction parameters, indicating the four alloying elements are not lightly dissolved in Ir matrix. The elastic properties of Ir are consistent with available experiment and other theory studies. The bulk modulus of dilute Ir-based alloys decreases with increasing of atomic radius of solute in full relaxing strategy, while the bulk modulus has a revered trend in atom relaxing strategy. Ir31Th has the best ductility and Ir31Tc has the highest hardness in full relaxing strategy. Nonetheless, the most Ir31X are brittleness after doping alloying elements. Through electronic structure analysis in full relaxing strategy, the reason why Ir31Th has the best ductility is that the electron cloud shows spherical distribution after Th doped in (100) plan and there are the lowest mean bond population and longest mean bond length between Th and Ir, While the reason why Ir31Tc has the highest hardness is that the degree of delocalization of electron cloud is the largest around Tc and there is the shortest mean bond length between Tc and Ir, indicating the stronger ionic between Tc and Ir. Besides, calculation of phase diagrams (CALPHAD) is employed to construct the composition-dependent elastic properties model for Ir-X binary alloys. which can be employed to describe the properties of Ir-based multicomponent alloys.

Synthesis of nano-ZIF-8@chitosan microspheres and its rapid removal of p-hydroxybenzoic acid from the agro-industry and preservatives

p-Hydroxybenzoic acid is an emerging contaminant because it has multiple sources such as the hydrolysis of methylparaben, ethylparaben and propylparaben used widely as preservatives in food and drinks, and as well as from the agro-industrial wastewaters. In this study, the nano-ZIF-8@chitosan microspheres (ZIF-8@CSM) were fabricated via the combination of inverse emulsion method and in-situ growth method. The performance of ZIF-8@CSM for the adsorption of p-hydroxybenzoic acid from aqueous solution was studied. The adsorption kinetics showed that the adsorption rapidly reached the equilibrium about 30 s. The equilibrium data were well described by the Langmuir isothermal model and the estimated maximum adsorption capacity was 128.70 mg/g. The thermodynamics analysis indicated negative free energy, enthalpy, and entropy changes suggesting that the adsorption process was spontaneous and exothermic. ZIF-8@CSM is promising to be used as a good adsorption material to remove p-hydroxybenzoic acid rapidly from aqueous solutions.

Simulating Thermodynamic Stabilization in Nanocrystalline Binary Alloys Using a Novel Cellular Automaton Model

Predictive models for grain growth of nanocrystalline binary alloys are designed to select appropriate solutes and assess thermodynamic stabilization in nanoscale alloy systems. The available models incorporate concepts of free energy, solute segregation, size-misfit elastic strain energy, grain boundary energy and phase field framework. Besides the above factors, the present work proposes a novel cellular automaton model by considering normal grain boundary (GB) diffusion, triple junction GB kinetics and grain misorientation. The experimental data for two kinds of binary alloy system were used to validate the reasonability of the proposed model. For nanocrystalline Fe-4% Zr alloy with large atomic size mismatch and negative mixing enthalpy, compared with the available models, the proposed model shows a better fit to the experimental results for grain size as a function of annealing temperatures. For another binary alloy system with small atomic size mismatch and positive mixing enthalpy, the proposed model also captures well the measurements for grain size of nanocrystalline W-20% Ti alloy. The comparisons reveal that the proposed model has a wide application in addressing the thermal stabilization of nanocrystalline grain size.

Calorimetric investigation of TmCl3-MCl liquid mixtures (M = Li, Na, K, Rb)

The molar enthalpies of mixing (ΔmixHm) in the liquid alkali chloridethulium (III) chloride mixtures have been measured with a Calvet-type high temperature microcalorimeter over the entire composition range at 1130 K. Mixing of the two liquid components was achieved by using the “break-off ampoule technique”. All the melts are characterized by negative enthalpies of mixing with a minimum value of approximately: 1.8, 10.3, 23.4, and 26.0 kJ·mol−1, for systems with LiCl, NaCl, KCl and RbCl, respectively. For all systems, the minimum of the enthalpy of mixing is shifted towards the alkali chloride-rich compositions and located in the vicinity of xTmCl3 ~0.350. The composition dependence of the interaction parameter λ, with a broad minimum at xTmCl3 ~0.2 for all of the systems is indicative of TmCl63− complexes formation in the melts. The results were discussed with using Papatheodoru-Østvold model of complexes formation and Associate Solution Model. The configurational mixing entropy of investigated systems has been calculated and commented.

Theoretical prediction, synthesis, and crystal structure determination of new MAX phase compound V2SnC

Guided by the theoretical prediction, a new MAX phase V2SnC was synthesized experimentally for the first time by reaction of V, Sn, and C mixtures at 1000 °C. The chemical composition and crystal structure of this new compound were identified by the cross-check combination of first-principles calculations, X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), and high resolution scanning transmission electron microscopy (HR-STEM). The stacking sequence of V2C and Sn layers results in a crystal structure of space group P63/mmc. The a- and c-lattice parameters, which were determined by the Rietveld analysis of powder XRD pattern, are 0.2981(0) nm and 1.3470(6) nm, respectively. The atomic positions are V at 4f (1/3, 2/3, 0.0776(5)), Sn at 2d (2/3, 1/3, 1/4), and C at 2a (0, 0, 0). A new set of XRD data of V2SnC was also obtained. Theoretical calculations suggest that this new compound is stable with negative formation energy and formation enthalpy, satisfied Born-Huang criteria of mechanical stability, and positive phonon branches over the Brillouin zone. It also has low shear deformation resistance c44 (second-order elastic constant, cij) and shear modulus (G), positive Cauchy pressure, and low Pugh’s ratio (G/B = 0.500 < 0.571), which is regarded as a quasi-ductile MAX phase. The mechanism underpinning the quasi-ductility is associated with the presence of a metallic bond.

Cu2Zn(Si,Ge)Se4 quaternary semiconductors as potential photovoltaic materials

The geometric and electronic structures of Cu2ZnSixGe1-xSe4 alloys are studied using density functional theory calculations. The variation of lattice constants is less than 1.2%. Negative formation enthalpies are obtained, indicating these alloys are completely miscible. The conduction band minimum gradually shifts upward with the Si concentration, resulting in a tunable bandgap from 1.27 to 2.26 eV. The bandgap of the Cu2ZnSi0.25Ge0.75Se4 alloy is very close to the optimal value. Compared with other two well-studied alloys with the optimal bandgap (Cu2ZnSi0.5Sn0.5Se4 and Cu2ZnSnS4), the Cu2ZnSi0.25Ge0.75Se4 has a red-shift in the optical absorption edge, highest absorption coefficient and smallest transmittance.

Efficient adsorbent derived from Argania Spinosa for the adsorption of cationic dye: Kinetics, mechanism, isotherm and thermodynamic study

In this paper, the wood powder from the shell of Argan nuts was used in raw form, or modified form by Sodium hydroxide, as a new economic and ecologic adsorbent. The effectiveness of these materials was evaluated on Methylene Blue (MB), a cationic dye. Those adsorbents were characterized by using scanning electron microscopy (SEM) and Fourier transformed infrared spectroscopy (FTIR). The effect of contact time (2-180 min), adsorbent dose (0.02- 0.8 g), initial dye concentration (50-500 mg/L), pH (2-10.5), and temperature (24-50°C) on the adsorption capacity was studied in a batch reactor. Result obtained showed that the process of MB adsorption onto both adsorbents is in good agreement with the Langmuir adsorption isotherm (R²=0.99 and qe, exp ≈ qe, cal=14.28 for ASN and 64.62 mg/g for ASNN) and followed the pseudo-second-order kinetic model (R²≈1 and qe, cal ≈ qe, exp). According to the equilibrium study, MB was better adsorbed on the modified powder (Qmax ≈ 70 mg/g) than on the raw powder (Qmax ≈ 14 mg/g). The thermodynamic study gives a negative enthalpy (- 28.70 for ASN and - 60.45 KJ/mol for ASNN), a negative Gibbs free energy (- 13.0 for ASN and -16.5 KJ/mol for ASNN), and negative entropy (- 53.14 for ASN and - 148.04 J/mol/K for ASNN) That confirms that the adsorption reaction is energetically favorable, exothermic and spontaneous. We propose an adsorption mechanism-based to electrostatic attractions and H- bonding interaction. The modified adsorbent was found to be comparable or better than others already studied materials, because of its high adsorption capacity and in only 10 minutes of agitation and its efficiency even after five utilizations.

New Zirconium Diboride Polymorphs-First-Principles Calculations.

Two new hypothetical zirconium diboride (ZrB) polymorphs: (hP6-P6/mmc-space group, no. 194) and (oP6-Pmmn-space group, no. 59), were thoroughly studied under the first-principles density functional theory calculations from the structural, mechanical and thermodynamic properties point of view. The proposed phases are thermodynamically stable (negative formation enthalpy). Studies of mechanical properties indicate that new polymorphs are less hard than the known phase (hP3-P6/mmm-space group, no. 191) and are not brittle. Analysis of phonon band structure and density of states (DOS) also show that the phonon modes have positive frequencies everywhere and the new ZrB phases are not only mechanically but also dynamically stable. The estimated acoustic Debye temperature, , for the two new proposed ZrB phases is about 760 K. The thermodynamic properties such as internal energy, free energy, entropy and constant-volume specific heat are also presented.

Highly Selective Removal of Perfluorinated Contaminants by Adsorption on All-Silica Zeolite Beta.

Perfluorinated alkylated substances (PFASs) are widely used in industrial and commercial applications, leading to a widespread occurrence of these persistent and harmful contaminants in our environment. Removal of these compounds from surface and waste waters is being mandated by European and U.S. governments. Currently, there are no treatment techniques available that lower the concentrations of these compounds for large water bodies in a cost- and energy-efficient way. We hereby propose a hydrophobic, all-silica zeolite Beta material that is a highly selective and high-capacity adsorbent for PFASs, even in the presence of organic competitors. Advanced characterization data demonstrate that the adsorption process is driven by a very negative adsorption enthalpy and favorable steric factors.

Highly Selective Removal of Perfluorinated Contaminants by Adsorption on All‐Silica Zeolite Beta

AbstractPerfluorinated alkylated substances (PFASs) are widely used in industrial and commercial applications, leading to a widespread occurrence of these persistent and harmful contaminants in our environment. Removal of these compounds from surface and waste waters is being mandated by European and U.S. governments. Currently, there are no treatment techniques available that lower the concentrations of these compounds for large water bodies in a cost‐ and energy‐efficient way. We hereby propose a hydrophobic, all‐silica zeolite Beta material that is a highly selective and high‐capacity adsorbent for PFASs, even in the presence of organic competitors. Advanced characterization data demonstrate that the adsorption process is driven by a very negative adsorption enthalpy and favorable steric factors.

The investigation of electronic, anisotropic elastic and lattice dynamical properties of MAB phase nanolaminated ternary borides: M2AlB2 (M=Mn, Fe and Co) under spin effects

Abstract In the present study, the structural, electronic, magnetic, anisotropic elastic and lattice dynamic properties of the ternary metal borides M 2 A l B 2 ( M = M n , F e and C o ) known as MAB phases have been investigated by density functional theory. The obtained results from the structural optimizations show that all these compounds have negative formation enthalpy implying the thermodynamic stability and synthesizability. The spin effects on the M 2 A l B 2 phases have been studied with the plotted energy-volume curves for different magnetic phases (antiferromagnetic (AFM), ferromagnetic (FM), and paramagnetic (PM)) of these compounds. The stable magnetic phase for the M n 2 A l B 2 compound is found to be AFM while the magnetic nature of F e 2 A l B 2 and C o 2 A l B 2 compounds are FM. The calculated electronic band structures with the total and orbital projected partial density of electronic states imply that these ternary metal borides have metallic behavior. Also, the mentioned compounds have mechanical and dynamic stability due to the calculated elastic constants and the observed phonon dispersion curves. Some thermodynamic properties have been investigated by means of phonon dispersion curves. Furthermore, the anisotropic elastic properties have been visualized in three dimensions (3D) for Young’s modulus, linear compressibility, shear modulus, Poisson’s ratio, and sound wave velocities.