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SrO-borovanadate glasses with the nominal composition (V₂O₅)_z(SrO)_0.2( B₂O₃)_0.8-z, 0.4≤z ≤0.8 were studied by direct current (DC) electrical conductivity, inductively coupled plasma (ICP) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy and X-ray-powder-diffraction (XRD). These glasses were prepared by a normal quench technique and the actual compositions of the glasses were determined by ICP spectroscopy. XRD patterns confirm the amorphous nature of the present glasses. The temperature dependence of DC electrical conductivity of these glasses has been studied in terms of different hopping models. The IR results agree with previous investigations on similar glasses and it has been concluded that similar to SrO-vanadate glasses, metavandate chainlike structures of SrV₂O₆ and individual VO₄ units also occur in these SrO-borovanadate glasses. The SrV₂O₆ and VO_n polyhedra predominate in the low B₂O₃ containing SrO-borovanadate glasses as the B substitutes into the V sites of the various VO_n polyhedra and only when the B₂O₃ concentration exceeds the SrO content do BO_n structures appear. This qualitative picture of three distinct structural groupings for the Sr-vanadate and Sr-borovanadate glasses is consistent with the proposed glass structure on previous IR and extended X-ray absorption fine structure (EXAFS) studies on these types of glasses. The conductivity results were analyzed with reference to theoretical models existing in the literature and the analysis shows that the conductivity data are consistent with Mott's nearest neighbor hopping model. However, both Mott VRH and Greaves models are suitable to explain the data. Schnakenberg's generalized polaron hopping model is also consistent with the temperature dependence of the activation energy, but the various model parameters such as density of states, hopping energy obtained from the best fits were found to be not in accordance with the prediction of the Mott model.

The structure of the FeMo cofactor with the central X ligand (X = C^4-, C^2-, N^3-, N^-, or O^2-) has been determined by the density functional approach. The FeMo cluster with one of the proposed central atoms C^4-, C^2-, N^3-, or N^- has an optimized geometry, comparable with the high-resolution X-Ray crystallographic structure of the nitrogenase FeMo cofactor. When the O^2- species is present, the FeMo cofactor has an expanded cage. Calculations in the gas phase show that an >Fe₄ facet of the FeMo cluster binds NO and CO in end-on coordination with an exothermicity of 25 and 8 kcal mol^-1, respectively, while the singlet O₂ coordinates to the FeMo cluster with an endothermicity of 12 kcal mol^-1. Deoxygenization of the bound NO and CO by the proton-electron addition is favored energetically, which leads to penetration of the C or N atom into the FeMo cage and yields the FeMo(μ₆-X) cluster. Antiferromagnetic coupling between the Fe sites and vibrational properties of the FeMo(μ₆-X) cluster, as well as the Mo-bound homocitrate ligand ring opening, have been explored theoretically. Present results suggest that O^2- is unlikely as a central anion and the central ligands are identifiable by their IR spectra. Predicted energetics indicates that the protonation opening of the homocitrate ligand ring at the Mo site is feasible.

The formation mechanisms of pentafulvenone and azafulvenone were extensively investigated at the B3LYP/6-311++G** level and the potential energy surfaces were drawn out. Ketene pentafulvenone (A) and 3-carbonyl-3H-pyrrole (C) can be formed by eliminating N₂ from the diazo ketone via α elimination reaction and ketene 2-carbonyl-2H-pyrrole (B), 4-carbonyl-4H-imidazole (D), and 2-carbonyl-2H-imidazole (E) were formed by the elimination of water or methanol from pyrrole-2-carboxylic acid (rB) and carboxylate (rD and rE) via β elimination reaction. The structures of these monomers were compared and showed some information about the bond changed characters. The structure investigation indicated that the C=C bond is activated when the nitrogen atom locates in the ortho position of the C=C=O part, and therefore ortho-monomers are more facile to react. The difference of the amount and stability of the corresponding dimers are caused by differing the position and number of nitrogen atom and the variety of the ortho-dimer is complicated. In addition, the infrared spectra of the title species were also analyzed including the vibrational frequencies, IR relative intensities, and vibrational mode assignment.

The cyano (–CN), isocyano (–NC), nitramine (–NNO₂), and nitrate (–ONO₂) derivatives of HNS has been studied in this work at the B3LYP/6-31G* level of density functional theory. Their IR spectra were predicted and assigned by vibrational analysis. Based on the frequencies scaled by 0.96 and the principle of statistic thermodynamics, the thermodynamic functions were evaluated. It is found that the thermodynamic functions linearly increase with the number of –CN, –NC, –NNO₂, and –ONO₂ groups, as well as the temperature. The contribution of various substitutents to the thermodynamic functions has the order of –ONO₂ > –NNO₂ > –NC > –CN. Detonation properties were evaluated using the modified Kamlet–Jacobs equations based on the calculated densities and heats of formation. Compared with the commonly used explosives (RDX and HMX), 3,3′,5-trinitramine-2,2′,4,4′,6,6′-Hexanitrostilbene, 3,3′,5,5′-tetranitramine-2,2′, 4,4′,6,6′-Hexanitrostilbene, 3,3′,5-trinitrate-2,2′,4,4′,6,6′-Hexanitrostilbene, and 3,3′,5,5′-tetranitrate-2,2′, 4,4′,6,6′-Hexanitrostilbene have better detonation performance and may be potential candidates of high energy density compounds.

A quantum chemical investigation has been performed to spotlight the structure–property relationship among methoxybenzeylidene-based humidity sensor and water molecules. The chemical interactions among (E)-2-(4-(2-(3,4-dimethoxybenzeylidene)hydrazinyl)phenyl) ethane-1,1,2-tricarbonitrile (DMBHPET) sensor and water molecules have been studied using density functional theory (DFT) methods. The molecular structural parameters, binding energies and Infrared (IR) spectroscopic analyses have been performed to assess the nature of intermolecular interactions. Three different positions have been identified for possible attachments of H₂O molecules through hydrogen bonding interactions. These positions include NH (complex 1a), p-OCH₃ (complex 1b) and N=N (complex 1c) group in sensor molecule (1) for the chemical adsorption of water molecules. While, the complex 1abc includes all three sites with simultaneously three H₂O molecules attached to it through hydrogen bonding. The binding energies calculated for complex 1a(NH…H₂O), complex 1b(CH₃O…H₂O), complex 1c(N=N…H₂O) and complex 1abc are -30.97, -18.41, -13.80 and -65.36 kcal/mol, respectively. The counterpoise (CP) scheme has been used to correct the basis set superposition error (BSSE) in calculation of binding energies of sensor and H₂O complexes. The higher binding energy of -65.36 kcal/mol for complex 1abc represents that the present methoxybenzeylidene-based sensor has significant potential through hydrogen bonding formation for sensing humidity as indicated in our previous experimental investigation. The evidence of hydrogen bonding interactions between sensor 1 and H₂O molecules has been traced through structural parameters, red shift in IR spectra as well as molecular electrostatic maps. Thus the present investigation highlights the first computational framework for a molecular level structure-binding activity of a methoxybenzeylidene-based sensor and water molecules.

In the present work, a theoretical study of the geometrical structures and spectroscopic (IR, ¹H and ${}^{13}$C NMR, UV-visible) properties, and anti-cancer activity of cis-fused tetrahydrochromeno[4,3-b]quinolines have been performed. The equilibrium geometries have been optimized at the B3LYP/6-31G(d) computational level and the present study puts in evidence the stability preference of the cis stereoisomers in comparison with the trans ones as expected experimentally. The vibrational frequencies and IR spectra were calculated at the same level of theory and compared to experimental FT-IR spectra and the spectral peaks have been assigned on the basis of potential energy distribution results. UV-visible absorption bands were calculated using the TD-DFT/B3LYP/6-31G(d) method. The ${}^{13}$C nuclear magnetic resonance chemical shifts and the coupling constants were calculated at the B3LYP level using the gauge independent atomic orbital (GIAO) method in chloroform solvent. The ¹H chemical shifts were calculated using the recently proposed WP04/6-31G(d) DFT functional. The visualization of the molecular electrostatic potential (MEP) surfaces and the docking simulation show that the absence of the methyl group at 2-position of tetrahydrochromeno[4,3-b]quinoline moiety is responsible of the potential anti-cancer activity of this compound.