Functional Theory Method Research Articles

Predicting Autoxidation of Sulfides in Drug-like Molecules Using Quantum Mechanical/Density Functional Theory Methods.

Autoxidation of drugs and drug-like molecules is a major concern in the development of safe and effective therapeutics. Because active pharmaceutical ingredients (APIs) that contain sulfur atoms can form sulfoxides under oxidative stress, predicting oxidative susceptibilities within an organic molecule can have a major impact in accelerating the compound's stability assessment. For investigation of a sulfur atom's oxidative stability, density functional theory (DFT) methods were applied to accurately predict S-O estimated bond dissociation enthalpies (BDEs) of sulfoxides. Our process employed B3LYP/6-31+G(d) for geometry optimization and frequency calculation, and we employed B3P86/6-311++G(2df,2p) to obtain electronic energies from single-point energy calculations. A total of 84 drug-like molecules containing 50 different sulfide scaffolds were used to develop a risk scale. Our results showed that when S-O BDE is less than 69 kcal/mol, the sulfur atom has low oxidative susceptibility. High oxidation risk occurs when the S-O BDE is greater than 75 kcal/mol. The risk scale was successful in predicting the relative propensities of sulfide oxidation among the small organic molecules and commercial drugs examined.

On a numerical-analytical method for constructing extremal polynomials of a complex argument

This article is devoted to the development of a numerical-analytical method for constructing extremes in the Chebyshev norm polynomials, given on the square of the complex plane. The studied polynomials are a generalization of the classical Chebyshev polynomials of the first kind. In the complex case there are no classical Chebyshev alternance conditions, and the Kolmogorov criterion along with the Ivanov – Remez criterion are difficult to prove for establishing the extremality property of specific polynomials. On the basis of the subdifferential construction developed by the authors of the article the extremal polinomials on the squares of the complex plane are calculated in an explicit way. The basic research methods are the methods of functional and complex mathematical analysis, as well as the Maple 2021 computer mathematics system. Methods of function theory and some general results of optimization theory are also used.

Investigation of CdSe and ZnSe as Potential Back Surface Field Layers for CdTe‐Based Solar Cells: A Study from First Principles Calculations

AbstractA class of II–VI semiconductors, especially CdTe, is a highly photo‐reactive compound that would be suitable for photovoltaic applications. However, being a highly resistive material, CdTe produces considerable contact resistance and drastically reduces the efficiency of photovoltaic devices. Introducing a back surface field layer at the contact region may significantly improve the device's performance. This work investigates the suitability of using ZnSe and CdSe layer as a back‐surface‐field layer in CdTe‐based solar cells through accurate electronic structure calculations using the hybrid‐density functional theory method. The calculations show that both ZnSe/CdTe and CdSe/CdTe behave as type‐II heterojunctions with band gaps of 2.0 and 1.1 eV, respectively. The Mulliken electronegativity method is used to determine the correct band edge positions concerning the vacuum level for all the pristine semiconductors and their interfaces. Calculation shows that a significant charge redistribution in the interface leads to the formation of an effective local field near the contact region for both ZnSe/CdTe and CdSe/CdTe heterostructures. This local field may help to separate the photogenerated electron–hole pairs in the active layer by pushing the opposite charges into the two different sections of the heterojunction. Additionally, the heterojunctions also exhibit better light‐absorption characteristics in the visible light range.

Synthesis, spectroscopic, and density functional theory studies of the corrosion inhibitive behaviour of n-(1,4-dihydro-1,4-dioxonaphthalene-3-yl)pyrazine-2-carboxamide chelator-ligand

The inhibitory effect of N-(1,4-dihydro-1,4-dioxonaphthalene-3-yl) pyrazine-2-carboxamide (HL chelator) on the corrosion of mild steel (Ms) in 1M HCl remained appraised via weight loss (WL) estimations, atomic absorption spectrophotometer (AAS), scanning electron microscope (SEM) and computational studies. The adsorption of the appraised ligand remained found to conform to Langmuir adsorption isotherm (LAI). The data acquired for ΔGads denotes chemisorption adsorption mechanism for the inhibitor while acquired AAS analysis results revealed that the concentration of iron in the inhibited corrosive medium is less than the concentration of iron in the uninhibited solution after immersion with Ms at the same contact time and was also observed to reduce with upsurge in concentration of the inhibitor. SEM micrographs acquired revealed that the existence of the studied compound lessened the degree of corrosion in addition to decreased surface roughness signifying establishment of protective inhibitor film at the Ms surface. The energy of highest occupied molecular orbital (EHOMO) as well as energy of lowest unoccupied molecular orbital (ELUMO) remained estimated via density functional theory (DFT) method from which other parameters were determined. The results acquired from computational studies were in conformity with those from experimental studies and both validate the use of HL chelator as an excellent and efficient inhibitor for the corrosion of Ms in 1 M HCl.

A Theoretical Study on the Medicinal Properties and Eletronic Structures of Platinum(IV) Anticancer Agents With Cl Substituents.

In this paper, we selected Pt(en)Cl4, Pt(dach)Cl4, and Pt(bipy)Cl4 with gradually increasing ligands to explore the ligand effect on the properties of platinum(IV) anticancer drugs. The electronic structures and multiple drug properties of these three complexes were studied at the LSDA/SDD level using the density functional theory (DFT) method. By comparing the gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO), electron affinity, atomic charge population, and natural bond orbital (NBO), we found that the order of reducibility is Pt(bipy)Cl4 > Pt(en)Cl4 > Pt(dach)Cl4. Our research can provide the theoretical basis for the development of anticancer drugs.

First-principles studies on electronic structure and optical properties of two-dimensional ZrO2

Two-dimensional 1T-ZrO2 material is investigated via first-principles calculations based on density functional theory (DFT) method. The band gap of cubic, tetragonal and monoclinic ZrO2 is 6.095 eV, 5.784 eV and 5.835 eV respectively obtained in the paper also. [Formula: see text] method is determined to adopt to study two-dimensional 1T-ZrO2 in the paper. The results show that the band gap of 1T-ZrO2 material is 7.513 eV and it is an indirect wide band gap semiconductor structure. At the same time, it can be seen from the density of states (DOS) that the valence band of the 1T-ZrO2 material is mainly due to the contribution of 2p electron of O atom. 4p, 4d and 5s electron of Zr atom also contributes a little to the valence band. 4p, 4d, 5s electron of Zr atom and 2s, 2p electron of O atom contribute to the conduction band, but main contribution has come from 4d of Zr atom. These results are in good agreement with the electron orbitals diagram. 1T-ZrO2 material has maximum reflectivity of 11.61% and refractive index of 1.62. It has high absorption coefficient and energy loss in this region. The peak of dielectric function may be mainly caused by the inter-band transition from electron-occupied state to non-occupied state. The real part of the photoconductivity tends to zero in the visible region with low energy and the maximum conductivity of 2.087 corresponds to the peak of other photoelectric properties of 1T-ZrO2 material.

High-Resolution Color Transparent Display Using Superimposed Quantum Dots.

In this paper, a high-resolution full-color transparent monitor is designed and fabricated using the synthesized quantum dots for the first time. For this purpose, about 100 compounds that had the potential to emit blue, green, and red lights were selected, and simulation was performed using the discrete dipole approximation (DDA) method, in which the shell layer was selected to be SiO2 or TiO2 in the first step. Among the simulated compounds with SiO2 or TiO2 shells, Se/SiO2 and BTiO3/SiO2 were selected as blue light emitters with high intensity and narrow bandwidth. Accordingly, CdSe/SiO2 nanoparticles were selected as green light emitters and Au/TiO2 for the red light. As the surface of the nanoparticles in their optical properties is important, reactivation of the nanoparticles’ surface is required to reach the high-intensity peak and resolution. To this end, in the second step, the surface of Se and CdSe nanoparticles reacted with ethanolamine, which can make a strong bond with cadmium atoms. The band structure and optical properties were obtained by the density functional theory (DFT) method. The Se/Ethanolamine and CdSe/Ethanolamine were experimentally synthesized to evaluate the theoretical results, and their optical properties were measured. To fabricate a transparent monitor, Se/Ethanolamine, CdSe/SiO2, and Au/TiO2 nanoparticles were dispersed in polyvinyl alcohol (PVA) solved in water and deposited on the glass by the doctor blading technique. Finally, high-resolution videos and images were displayed on the fabricated monitor.

Flotation Performance and Adsorption Mechanism of a Novel Chelating Collector for Azurite

Thiophosphate compounds have attracted much attention in coordination chemistry, but their deep adsorption mechanism remains underexplored as flotation collectors. The flotation performance and adsorption mechanism of a novel (dibutoxy-thiophosphorylsulfanyl)-acetic acid (CDDP) chelating collector on azurite surfaces were studied by micro-flotation tests, zeta potential measurements, and Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FE-SEM) analysis. The micro-flotation results indicated that CDDP exhibited superior collecting performances to direct flotation recovery of azurite and floated over 91.44% of azurite at pH 7. For sodium isopentyl xanthate (NaIX) and Benzohydroxamic acid (BHA) collectors, the addition of Na2S still did not show good collection performance. The results of zeta potential, FTIR, XPS and FE-SEM measurements, all confirmed that CDDP showed a better affinity to azurite surfaces than NaIX and BHA. Furthermore, XPS and FE-SEM provided obvious evidence that CDDP could easily react with Cu2+ sites on azurite surfaces. Using the density functional theory (DFT) method, the collection capacity of azurite was CDDP > BHA > NaIX, which exactly matched the micro-flotation results. In addition, this study provided an atomic-scale understanding of the structure–property relationship of CDDP as chelating agents for copper mineral flotation.

Effect of FA: X+3 (X = B, Al, and Ga) Color Centers on the Electronic and Optical Properties of LiF (001) Surface

The density functional theory and configuration interaction single excitations methods were used to study the effect of FA color centers on the electronic and optical properties of the LiF (001) surface. Three types of FA color centers were used, FA: B+3, FA: Al+3, and FA: Ga+3. The evaluated values of the ionization potential, chemical hardness, and softness indicate the stability of the investigated color centers. FA: B+3 is the most stable one. While the electron affinity values reveal that the FA: Al+3 center is the highest reactive one. The Ultraviolet-Visible spectra for FA: B+3, FA: Al+3, and FA: Ga+3 centers showed that the scrutinized centers have two absorption peaks. The highest absorption peak recorded for FA: B+3 center is located at 285 nm, while the highest absorption peaks recorded for FA: Al+3, and FA: Ga+3 centers are located at 173 and 165 nm, respectively. According to the light-harvesting efficiency values, FA: Al+3, and FA: Ga+3 centers have the highest efficiency to gather the energy during the pumping process than FA: B+3 centers. Stokes-shift values for FA: B+3, FA: Al+3, and FA: Ga+3 centers were 0.16, 0.37, and 0.33 eV, respectively, consequently, FA: Al+3 and FA: Ga+3 centers, are more suitable for laser production than FA: B+3 center.

Synthesis, crystal structure, Hirshfeld surface analysis and molecular docking analysis of new cadmium(II) iodide complex with the pyridine, 4-(1,1-dimethylethyl)

This study was set out to introduce a newly synthesized cadmium complex, [Cd(4-tertbutyl-pyridine)2I2], where t-BP = 4-tert-butyl pyridine. The complex was synthesized and characterized using elemental analysis, X-ray diffraction, FTIR, and photoluminescence combined with DFT calculations. The X-ray analysis of (Cd(t-BP)2I2) revealed that the Cd center is approximately tetrahedrally coordinated with two nitrogen atoms from the 4-tertbutylpyridine groups and the two I ions forming an approximately tetrahedral geometry with τ4 = 0.89. The presence of various intermolecular interactions and 2 D-fingerprint regions is supported by the Hirshfeld surface analysis. In the theoretical calculations, the density functional theory (DFT) method with the PBEPBE functional, the SDD basis set for Cd and I, and the 6-311 G(d) basis set for C, N, and H at the B3LYP/LANL2DZ level were chosen as the computational method. Systems based on electronic and optical properties were also discussed. The frontier molecular orbitals (FMO) analysis, chemical activity, local reactivity descriptors (Fukui functions), and NLO properties were examined for the compound at the LANL2DZ level of theory. The Cd(II) complex was studied by using molecular docking analysis to identify the active site and binding energies with anti-cancer receptors.

Application of Polarisable Continuum Modelling to assess Minoxidil solubility in mixed solvents

ABSTRACT Experimental solubility of minoxidil was obtained in binary aqueous mixtures of ethanol, methanol and acetonitrile at 298.2 K. The effects of pH and micellisation were investigated on the solubility of the drug. Experimental solubility data was correlated by three co-solvency models, i.e. Yalkowsky, CNIBS/R-K, and the modified Wilson model. Density functional theory and hybrid functional B3LYP method was used with Polarisable Continuum Model (PCM) to correlate the experimental solubility data in various mass fractions of the binary solvent mixtures. We report the results of solute–solvent interaction energy as free energy of solvation (∆G sol ) of minoxidil in various mass fractions of ethanol + water mixtures. Total electrostatic energy, dipole moment, total Gibbs free energy and dielectric constant (ε) of minoxidil were also investigated.

Synthesis, crystal structure, spectral, thermal, dielectric, z-scan analysis and computational studies of 8-hydroxyquinolinium trichloroacetate (8HQTC)

An organic third-order nonlinear optical single crystal of 8-hydroxyquinolinium trichloroacetate (8HQTC) has been broughten about by proton transfer reaction established by slow evaporation method. Single crystal X-ray diffraction analysis profoundly revealed the crystal structure of 8HQTC in monoclinic system with the space group of C2/c. 8-hydroxyquinolinium (8HQ+) cations are linked to trichloroacetate (TCA- ) anions forming an ion pairs through these hydrogen atoms H6 of N1 and H5 of O1 in the form of N1__H6···O3 and O1__H5···O3 intermolecular hydrogen bonds in the unit cell that produce ring R4 2 (14) motif. The vibrational (FTIR and FTRaman)andopticaltransmittance(UV-Vis-NIR) spectral analysis were efficaciously carried out for 8HQTC crystal. TG-DTA analysis of grown material revealed the thermal stability upto 140 °C. The Frequency and temperature dependent dielectric constant and dielectric loss of the grown crystal was analysed. The nonlinear optical properties such as nonlinear refractive index (n2=8.36 x 10-12 m 2 /W) , nonlinear absorption coefficient (β=5.69 x 10-6 ) and third order susceptibility (χ(3) = 4.51 x 10-5 esu) values have been calculated for grown 8HQTC crystal using Z-scan measurements. The correlation between molecular structure of 8HQTC and its molecular perspectives has been accomplished by density functional theory (DFT) method.

Theoretical study of the stability and reactivity of salicylic acid isomers by the DFT method

The FT-IR spectrum of salicylic acid (SA) was studied in the region 10-4000 cm-1. The optimized molecular geometry and fundamental vibration frequencies are interpreted using structural optimizations based on the Functional Density Theory (DFT) method. Additionally, we used B3LYP / 6-311G (d, p) to determine the chemical descriptor, the ionization potential (I), the electron affinity (A), the chemical potential (μ), the chemical hardness (η). Nonlinear optical descriptors (NLO) such as dipole moment (μ), polarizability (α), first hyperpolarizability (β) and second hyperpolarizability (γ), 3D maps of HOMO and LUMO orbitals, lengths and Bond angles of salicylic acid isomers are also determined by both DFT and MP2 (The Møller-Plesset theory of order 2 perturbation) methods. The overall descriptors and the non-linear optical properties confirmed that salicylic acid is the reactive molecule and para-hydroxybenzoic acid is the stable molecule. An electrostatic molecular potential (MEP) study was also performed to determine the reactivity of molecules.

Theoretically studying the optoelectronic properties of oligomers based on 2.7-divinyl-cabazole

This work consists of theoretically studying the electronic and optical properties of 9-(4-octyloxyphenyl)-2.7-divinyl-carbazole (PCrV) oligomers. This study has been undertaken using the density functional theory (DFT) method at the B3LYP/6-31G (d,p) level and BP86/6-31G (d,p) level of theory. To evaluate the PCrV-basis systems properties, the structural optimization without geometrical restrictions was performed on the total potential energy surface (TPES). In order to ensure good absorption of radiation, the interest was in increasing the efficiency of the organic photovoltaic cell. For this effect, the (HOMO-LUMO) gap energy of such compounds was reduced in terms of geometric and electronic structure. The BP86 functional gives good results at the energy gap level, while other parameters using the B3LYP functional give the best results.

RESEARCH INTO SORPTION CONDITIONS OF 2-(4-SULFOPHENYLAZO)-1-AMINO-8-HYDROXYNAPHTHALENE-3,6-DISULFONIC ACID BY COMMERCIAL ANION EXCHANGER AB-17

To obtain a new modified sorbent, the conditions for maximum sorption of the chelate reagent 2-(4-sulfophenylazo)-1-amino-8-hydroxynaphthalene-3,6-disulfonic acid (SPAAHS) by a strongly basic AB-17 anion exchanger were selected. The conditions for modifying the anion exchanger were studied by spectrophotometric analysis on a Specord 210 Plus spectrophotometer from Analytik Jena. The influence of such factors as the acidity of the solution, the contact time of the sorbent with the sorbate, and the concentration of SPAAHS on the sorption process was analyzed. According to the saturation curves, the static capacity of the anion exchange resin for the sorbed reagent was established. Also, the description of the adsorption isotherm of SPAAHS with the AB-17 anion exchanger was performed using the models of Langmuir, Freundlich, Temkin and Redlich-Peterson. To calculate the value of the ABerage free energy of adsorption, the adsorption isotherm of SPAAHS with the AB-17 anion exchanger was processed using the Dubinin-Radushkevich model. On the basis of the results obtained, conclusions were made about the nature of the bond between the anion exchanger and the sorbed reagent. To prove the proposed mechanism of sorption of SPAAHS by the AB-17 anion exchanger by the density of functional theory (DFT) method, using the Orca 4.2.0 program, an estimated quantum-chemical calculation of the dissociation energies of various acidic functional groups according to which an exchange reaction is possible on the anion exchanger AB-17.

Quantum Chemical Calculations of 2-Methoxy-4-[(3-p-Methylbenzyl-4,5-Dihydro-1H-1,2,4-Trıazol-5-One-4-YL)Azomethine] Phenyl-2-Methylbenzoate Molecule

2-Methoxy-4-[(3-p-methylbenzyl-4,5-dihydro-1H-1,2,4-triazol-5-one-4-yl) azomethine] phenyl-2-methylbenzoate was optimized by using Density Functional Theory (DFT/B3LYP, B3PW91) methods (Frisch et al., 2009; Wolinski et. al., 1990). 1H-NMR and 13C-NMR isotropic shift values were calculated by the method of GIAO using the program package Gaussian G09 (Wolinski et al., 1990). Theoretical and experimental values were inserted into the grafic according to equatation of δ exp=a+b. δ calc. Experimental data obtained from the literature (Yüksek et al., 2018). The standard error values were found via SigmaPlot program with regression coefficient of a and b constants. Furthermore, the veda4f program was used in defining of IR data theoretically (Jamróz, 2004). Theoretically calculated IR data are multiplied with appropriate adjustment factors (Merrick et al., 2007) and the data obtained according to DFT(B3LYP, B3PW91) method are formed using theoretical infrared spectrum. Also, dipole moments, the HOMO-LUMO energy, ΔEg, total energy of the molecule, bond lengths and Mulliken charges, the molecular surfaces such as molecular electrostatic potential (MEP) and MEP contour maps, the total density, the electron density and the electrostatic potential were calculated with same method and functions.

The Investigation of Spectroscopic and Electronic Properties of 3-Ethyl-4-(4-cinnamoyloxybenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-one Compound Using Density Functional Theory and Hartree-Fock Basis Sets

In this study, we reported a combined experimental and theoretical study on 3-n-propyl-4-(3-cinnamoyloxybenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-one compound. The title compound was prepared and characterized by Uv-Vis, FT-IR spectra, 1H and 13C NMR. UV-visible absorption spectra and the stimulation contributions in UV-visible transitions were obtained with TD-DFT/B3LYP and TD-FF methods and 6-311G(d) polarizer set based on optimized structure. Calculated absorption wavelengths (λ), oscillator power (f) and excitation energies were compared with experimental values. The calculated IR data of compound were calculated in gas phase by using of 6-31G(d) basis set of B3LYP and HF methods and are multiplied with appropriate scala factors. Theoretical infrared spectrums are formed from the data obtained according to B3LYP method. In the identification of calculated IR data was used the veda4f program. The molecular geometry, gauge including atomic orbital (GIAO), Experimental and theoretical values were inserted into the graphic according to equitation of δexp=a+b. δ calc. The standard error values were found via SigmaPlot program with regression coefficient of a and b constants. Obtained results indicate that there is a good agreement between the experimental and theoretical data. Also, HOMO-LUMO analyses properties, Mulliken’s atomic charges, dipole moment and total energy of the title compound in the ground state were investigated by using Hartree-Fock (HF) and density functional theory (DFT/B3LYP) methods with 6-31G(d) basic set.

In English

The structure and energy characteristics of structures formed during arginine adsorption on silica surface from aqueous solution were studied by the density functional theory (B3LYP) method using a valence-split basis set 6-31++G(d,p) within the continuous solvent model (PCM) and supermolecular approximation. The equilibrium structural and energy parameters of the protonated arginine molecule in the gas phase dependent on the location of the hydrogen atom are considered including those of two possible zwitterions. The structure of the arginine ion Н2А+, which is formed when a proton attaches to a molecule or zwitterion of a given amino acid, has been elucidated. To determine the deprotonation constant of the carboxyl group in an acidic medium, the complexes of the arginine molecule (AH32+) in the state with undissociated and deprotonated carboxyl groups are considered. The simulation of the acid medium was performed by taking into account the interaction with two hydrated HCl ion pairs, which provided the protonation of the a-amino group and the nitrogen atom of amino group within the guanidine group. In the study on the interaction of an arginine molecule with silica surface in an aqueous medium, complexes containing a Si8O12(OH)7O– ion with a deprotonated silanol group, six water molecules, and an arginine molecule with a deprotonated carboxyl group were considered. It has been found that the arginine molecule is most likely to be adsorbed on slica surface with formation of hydrogen bonds between the hydrogen atoms of the a-amino group and the oxygen atom of the deprotonated silanol group. In this case, the formation of a hydrogen bond between the oxygen atom of the carboxyl group and the hydrogen atom of the neighboring silanol group is possible. Slightly less likely is adsorption of arginine molecules due to interaction of the guanidine group with silanol groups of the surface. According to the calculated data, the adsorption of the zwitterionic form of the arginine molecule from the aqueous solution is equally likely to occur due to interaction of silanol groups of silica surface with both the carboxyl group and the guanidine group.

Radiation-Induced Oxidation Reactions of 2-Selenouracil in Aqueous Solutions: Comparison with Sulfur Analog of Uracil.

One-electron oxidation of 2-selenouracil (2-SeU) by hydroxyl (●OH) and azide (●N3) radicals leads to various primary reactive intermediates. Their optical absorption spectra and kinetic characteristics were studied by pulse radiolysis with UV-vis spectrophotometric and conductivity detection and by the density functional theory (DFT) method. The transient absorption spectra recorded in the reactions of ●OH with 2-SeU are dominated by an absorption band with an λmax = 440 nm, the intensity of which depends on the concentration of 2-SeU and pH. Based on the combination of conductometric and DFT studies, the transient absorption band observed both at low and high concentrations of 2-SeU was assigned to the dimeric 2c-3e Se-Se-bonded radical in neutral form (2●). The dimeric radical (2●) is formed in the reaction of a selenyl-type radical (6●) with 2-SeU, and both radicals are in equilibrium with Keq = 1.3 × 104 M−1 at pH 4 (below the pKa of 2-SeU). Similar equilibrium with Keq = 4.4 × 103 M−1 was determined for pH 10 (above the pKa of 2-SeU), which admittedly involves the same radical (6●) but with a dimeric 2c-3e Se-Se bonded radical in anionic form (2●−). In turn, at the lowest concentration of 2-SeU (0.05 mM) and pH 10, the transient absorption spectrum is dominated by an absorption band with an λmax = 390 nm, which was assigned to the ●OH adduct to the double bond at C5 carbon atom (3●) based on DFT calculations. Similar spectral and kinetic features were also observed during the ●N3-induced oxidation of 2-SeU. In principle, our results mostly revealed similarities in one-electron oxidation pathways of 2-SeU and 2-thiouracil (2-TU). The major difference concerns the stability of dimeric radicals with a 2c-3e chalcogen-chalcogen bond in favor of 2-SeU.

Design and properties of a new family of wing-like and propeller-like multi-tetrazole molecules as potential high-energy density compounds.

Density functional theory (DFT) methods were employed to design a new family of wing-like and propeller-like multi-tetrazole molecules based on the combination of N-center multi-tetrazole and various energetic groups. The optimized geometry, electronic properties, and thermodynamics were calculated for investigating the molecular stability and chemical reactivity. Their energetic parameters including density, heats of formation, detonation properties, and impact sensitivity were extensively evaluated, and the effects of energetic groups were investigated as well. These newly designed wing-like and propeller-like multi-tetrazole molecules exhibit acceptable oxygen balance, moderate impact sensitivities, high density, excellent heats of formation, and good detonation performance. Especially, B3, B4, B5, and B6 are very helpful for enhancing their detonation performance (D ≥ 9500m·s-1, P ≥ 41 GPa) are promising candidates for new environmentally friendly HEDMs.