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Abstract A series of azinesulfonamide derivatives of long-chain arylpiperazines with variable-length alkylene spacers between sulfonamide and 4-arylpiperazine moiety is designed, synthesized, and biologically evaluated. In vitro methods are used to determine their affinity for serotonin 5-HT1A, 5-HT6, 5-HT7, and dopamine D2 receptors. X-ray analysis, two-dimensional NMR conformational studies, and docking into the 5-HT1A and 5-HT7 receptor models are then conducted to investigate the conformational preferences of selected serotonin receptor ligands in different environments. The bent conformation of tetramethylene derivatives is found in a solid state, in dimethyl sulfoxide, and as a global energy minimum during conformational analysis in a simulated water environment. Furthermore, ligand geometry in top-scored complexes is also bent, with one torsion angle in the spacer (τ2) in synclinal conformation. Molecular docking studies indicate the role of halogen bonding in complexes of the most potent ligands and target receptors.

Abstract Lead zirconate-titanate PbZr 0.70 Ti 0.30 O 3 ceramics doped with bismuth oxide has been investigated. Dielectric and optical measurements were performed to check the dopant influence on phase transitions and pre-transitional effects. It has been postulated that the temperature at which maximum permittivity occurs is not connected with structural phase transitions. [ABSTRACT FROM AUTHOR]

A new chemical synthesis route by a thermal decomposition of nitrates and acetates, preceded by solution displacement reaction, was successfully applied to obtain the YF 3 :1%RE (RE = Pr, Ho, Er and Tm) and LaF 3 :1%Pr nanocrystals. The samples were characterized by the following methods: X-ray diffraction, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), magnetic susceptibility thermal dependence measurements and electron paramagnetic resonance (EPR). The obtained YF 3 :1%RE (RE = Pr, Ho, Er and Tm) materials crystallized with orthorhombic symmetry, whilst LaF 3 :1%Pr exhibits hexagonal structure. Chemical composition determined by EDX, XPS and magnetic measurements was close to nominal formula. SEM images show the nanometric size of the grains. Surface contamination can be suggested to be responsible for the deterioration of the optical properties of the composites. [ABSTRACT FROM AUTHOR]

We report the single crystal growth of FeNi Te with nominal compositions x = 0.01, 0.025, 0.05 and 0.1 using a slow cooled melt technique. Cylindrical crystals 0.5 cm in diameter and 2 cm long were obtained. The initial characterization, done using single-crystal diffractometer, revealed that the lattice parameter a increases and c decreases with Ni content. The crystal structure refinement was performed in the P4/ nmm space group. Chemical analysis confirmed the presence of nickel in the system close to the nominal content. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

• In the series CaCoSi n O 2n+2 there are no phases with n = 3 and n = 4, despite their similarity to copper based materials, • the chemical shifts of the XPS lines and Si K absorption edges indicates that Si has weaker cationic character than in SiO 2 despite the same chemical environment, • DFT calculations allowed to interpret spectroscopic data. In a public space there are several reports of materials with general stoichiometry CaCoSi n O 2n+2. Pyroxene CaCoSi 2 O 6 is probably the best-known representative for n = 2 but not much is known about materials with n = 3 and n = 4. In this study, attempts were carried out to synthesize those phantom materials and it was found that they do not exist as a single phase. A quantitative XRD analysis revealed that their chemical composition is correct but the formula should be written as CaCoSi 2 O 6 + (n-2)SiO 2. Similar qualitative conclusions were drawn from investigation of magnetic (DC magnetometry) and electronic properties using X-ray Photoelectron Spectroscopy (XPS) and Si K edge X-ray Absorption Spectroscopy (XAS). Additionally, the DFT ab initio calculations were carried out to obtain electronic signature from band structure of CaCoSi 2 O 6. The apparent influence of the excess of SiO 2 on magnetic properties of this "series" can be understood in terms of presence and suppression of secondary phases like Ca 2 CoSi 2 O 7 , which form when the starting materials are not homogenized properly. Addition of surplus SiO 2 suppresses their formation leaving clear signature from CaCoSi 2 O 6 , which also can be synthesized from stoichiometric mixture using proper techniques. [ABSTRACT FROM AUTHOR]

Abstract: The X-ray absorption K-edges of sulfur in CuCr2−x Sb x S4 (x =0.3, 0.4, 0.5) have been measured and compared to linearized augmented plain wave (LAPW) numerical calculations. The near edge region is generated by magnetically polarized and hybridized S 2p energy levels and shows small change with increased Sb content, which can be attributed to the movement of Cr 3d spin-down states up on the energy scale. The LAPW result confirms this effect. Moreover, the calculations show that the antimony in those spinels is rather in +3 than in +5 valence state. The calculated magnetic moment on Cr equals to 2.72μ B. In EXAFS, there is no visible change between x =0.3 and 0.5 spectra, which indicates that the local structure does not change significantly. [Copyright &y& Elsevier]

Materials for ultrafast femtosecond lasers, CaGdAlO 4 (CGA) single crystals, undoped and doped nominally with 8% at. of Yb, were grown by the Czochralski method in [100] direction. X-ray analyses showed the ideal disorder on Gd/Ca sites. The decrease of unit cell volume for the crystal doped with Yb was observed. Magnetic measurements revealed that undoped and doped samples were paramagnetic. The real concentration of Yb was determined as 5% at. The XPS lines: O1s, Al2p and Ca2p are complex and they consist of the main line and additional lines at lower and higher binding energy. The intensities of additional lines decrease comparing the end and cone part of crystal, indicating an improvement of crystal structure during the growth process. XPS chemical analyses showed deficiency of Al and Ca and excess of oxygen. The oxygen excess may exist in two contributions: in one, to keep the charge neutrality as Gd-O x sheets between CGA; the second as interstitial oxygen, responsible for brownish coloration of crystals. Dielectric properties are close to values measured for similar compounds CaYAlO 4 , CaNdAlO 4 , and SrLaAlO 4. • The ideal disorder on Gd/Ca sites was confirmed by X-ray measurements. • The XPS O1s, Al2p and Ca2p lines are complex due to defects in crystal structure. • The charge neutrality might be ensured by Gd-O x sheets between CGA. • Defects narrow the energy band gap from 4.6 to 4 eV. [ABSTRACT FROM AUTHOR]

The modified sol-gel method was used to obtain of Y 4 Al 2 O 9 nanopowders co-doped with Tb, Yb cations. SEM microstructure examination proved that nanoscale grains were obtained in all samples. Complex lines of Y3d, O1s and Al2p were found in the photoelectron spectra. The XPS energy gap in the valence band was estimated as about 4.6 eV. Results of SQUID magnetometry measurements confirmed nominal concentration of the co-dopants. [ABSTRACT FROM AUTHOR]

Highlights: [•] SrLaAlO4: Mn nano and single crystals were examined by XRD method to determine the crystal structure. [•] SEM/EDX imaging has been done. [•] XPS electronic structure was examined and discussed. [•] Experimental effective magnetic moment and the calculated one were compared. [Copyright &y& Elsevier]