Crystal Characterization of Anionic Salt Compounds as Composite of Solid Propellant Oxidizing Agent

Composite solid propellants are preferred for use in defense and space applications because of their high energy density and simplicity. Oxidizers take up the highest percentage in propellant ingredient. KNO3, KClO4 and K2Cr2O7 are among the inorganic oxidizers with similar cation for present study, and their chemical and physical properties are fully understood. However, the relationship between thermal stability and electrostatic potential energy based on structural analysis has not yet been studied. In this study we used high resolution XRD data to study the electrostatic potential energy of the KNO3, KClO4 and K2Cr2O7 crystal structures.

Revisiting the valence stability and preparation of perovskite structure type oxides ABO3 with the use of Madelung electrostatic potential energy and lattice site potential

The stability of perovskite structure type oxides and higth valence state of cations, respectively may be better understood by considering lattice site potential and Madelung electrostatic potential energy.

Supramolecular synthon hierarchy in sulfonamide cocrystals with syn-amides and N-oxides

Sulfonamide drugs are well known antibacterial and antimicrobial molecules for pharmaceutical development. Building a library of suitable supramolecular synthons for the sulfonamide functional group and understanding their crystal structures with partner coformer molecules continues to be a challenge in crystal engineering. Although a few sulfonamide cocrystals with amides and N-oxides have been reported, the body of work on sulfonamide synthons is limited compared with those that have carboxylic acids and carboxamides. To address this structural gap, the present work is primarily focused on sulfonamide–lactam and sulfonamide–syn-amide synthons with drugs such as celecoxib, hydrochlorothiazide and furosemide. Furthermore, the electrostatic potential of previously reported cocrystals has been recalculated to show that the negative electrostatic potential on the lactam and syn-amide O atom is higher compared with the charge on carboxamide and pyridine N-oxide O atoms. The potential of sulfonamide molecules to form cocrystals with syn-amides and lactams are evaluated in terms of the electrostatic potential energy for the designed supramolecular synthons.

Influence of Hydroxyl Functional Group on the Structure and Stability of Xanthone: A Computational Approach

The present work addresses computational research focused on the energetic and structural properties of four isomers monohydroxyxanthone, using the G3(MP2)//B3LYP method, in order to evaluate the influence of the hydroxyl (—OH moiety) functional group on the xanthone molecule. The combination of these computational results with previous experimental data of these compounds enabled the determination of their enthalpies, entropies and Gibbs energies of formation, in the gaseous phase, and consequently to infer about the relative thermodynamic stability of the four isomers. Other issues were also addressed for the hydroxyxanthone isomers, namely the conformational and the tautomeric equilibrium analysis of the optimized molecular structures, the frontier orbitals, and the electrostatic potential energy maps. Complementarily, an energetic study of the intramolecular O — H ⋯ O hydrogen bond for 1-hydroxanthone was also performed.

An analytical investigation of the cylindrical capacitor in the framework of a two-parameter modification of Born–Infeld electrodynamics

Iacopini and Zavattini [Vacuum polarization effects in the [Formula: see text] atom and the Born–Infeld electromagnetic theory, Nuovo Cimento B 78 (1983) 38–52] proposed a [Formula: see text]-two-parameter modification of Born–Infeld electrodynamics, in which the classical self-energy for an electron takes a finite value for [Formula: see text]. In this paper, we want to study a cylindrical capacitor from the viewpoint of Iacopini–Zavattini nonlinear electrodynamics analytically. The capacitance, the electrostatic potential energy, and the potential difference between the plates of a cylindrical capacitor are calculated in the framework of Iacopini–Zavattini electrodynamics for two specific values of [Formula: see text] and [Formula: see text]. The study of the behavior of a nonlinear cylindrical capacitor in the weak electric fields shows that our results are compatible with the correspondence principle, i.e. we recover the results of Maxwell electrodynamics in the weak field regime. Finally, the invariance of Iacopini–Zavattini nonlinear electrodynamics under the duality transformation is investigated.

Novel Thiazole Derivatives of Medicinal Potential: Synthesis and Modeling

This paper reports on the synthesis of new thiazole derivatives that could be profitably exploited in medical treatment of tumors. Molecular electronic structures have been modeled within density function theory (DFT) framework. Reactivity indices obtained from the frontier orbital energies as well as electrostatic potential energy maps are discussed and correlated with the molecular structure. X-ray crystallographic data of one of the new compounds is measured and used to support and verify the theoretical results.