ZnTe6O13, a new ZnO–TeO2 phase

Our investigations into the ZnO–TeO₂ system have produced a new phase, zinc(II) hexatellurium(IV) tridecaoxide, ZnTe₆O₁₃, with trigonal (R) symmetry, synthesized by repeated heating and cooling to a maximum temperature of 1053 K. The asymmetric unit consists of a Zn atom coordinated in a distorted octahedral fashion by two unique tellurium(IV) oxide units that form trigonal–bipyramidal TeO₄ and TeO₃₊₁ corner‐ and edge‐shared polyhedra. Except for the Zn and an O atom, which occupy 6c positions, all atoms occupy 18f general positions.     

Observation on Symmetry Properties of Sodium Zinc(II)-2,9,16,23-phthalocyanine Tetracarboxylate in Water:NaOH Solution

The shift of the Q-band of sodium zinc(II)-2,9,16,23-phthalocyanine tetracarboxylate (ZnPc(COONa)₄) to about 800 nm is attributed to the influence of the electron-donating property of the carboxylate groups substituted in the β–position. ZnPc(COONa)₄ which was found to have a symmetry of D _2h characterized by a splitting of the Q transition. This splitting was interpreted by the formation of dianionic symmetric ZnPc(COONa)₄ resulting from the dissociation of the pyrrole protons as well as the possibility of Na⁺ dissolution of ZnPc(COONa)₄ in the aqueous solution of NaOH.     

Crystallographic Analyses of High-Z Value Structure of a Pyridinium–Carboxylate Complex

Abstract  

Equimolar amounts of the proton acceptor 2-aminopyridine 1 and proton donor picolinic acid 2 were solvent-free grinded to give complex 5. X-ray diffraction was used to determine the crystal structure of the new complex 5 that found to be ionic, with proton transfer occurring to the aromatic nitrogen of the 2-aminopyridine moiety. Nonclassical hydrogen bonding exist in the solid state structure of 5, such as, 2-aminopyridine-carboxylic acid supramolecular heterosynthon was carefully investigated and compared to those exist in cocrystals in terms of supramolecular chemistry and crystal engineering. Complex 5 crystallizes in the monoclinic P2(1)/n space group with unit cell parameters of: a = 8.7714(12) ?, b = 12.1579(17) ?, c = 10.8546(15) ?, with α = 90°, β = 110.100(4)°, γ = 90°, and Z = 4.     

Structural and Antimicrobial Activity Analyses of Different Forms of Sulfur-Nitrogen Containing Heterocyclic Supramolecule

Abstract  

Direct crystallization of sulfur-nitrogen containing heterocyclic supramolecule I from acetic acid (solvent free) or in presence of an inert solvent afforded the proton-transfer compound III. The presence of nitrogen and sulfur atoms enhanced the solid-state packing of III to adopt interesting supramolecular interactions such as; S···H, S···N, N···O, O···H, S···H. Compounds I and III inhibited the growth of the Gram positive bacteria, B. subtilis and M. luteus.     

Study of interface mixing induced by Ar<Superscript>+</Superscript> ion irradiation on Ag–Ge bilayer system

A 400 keV ⁴⁰Ar⁺ ion beam was utilized to induce mixing between two thin layers of Ag and Ge. Rutherford Backscattering Spectrometry and Electrical Resistivity Measurements were employed as probes to investigate the kinetics of ion mixing. The intermixed region was studied at several fluences up to 1.7×10¹⁷ ions/cm² at a constant flux of 0.25 μA/cm². The “RUMP” simulation computer code was used to assist in the evaluation of the experimental results from the spectra. The analysis of the Rutherford Backscattering Spectrometry spectra shows that increasing the Ar⁺ fluence enhances the Ag–Ge intermixing. To describe the mixing process, mixing rate parameters were calculated and compared with the theoretical models’ predictions. Børgesen’s local thermal spike model was found to accurately predict the diffusion in the Ag–Ge interface. An increase in the electrical resistivity of the film was detected during irradiation.