Structural and Luminescence Behavior of Nanocrystalline Orthophosphate KY(PO): Eu ( = Ca, Sr) Synthesized by Hydrothermal Method.

KY(PO):5% Eu phosphates have been synthesized by a novel hydrothermal method. Spectroscopic, structural, and morphological properties of the obtained samples were investigated by X-ray, TEM, Raman, infrared, absorption, and luminescence studies. The microscopic analysis of the obtained samples showed that the mean diameter of synthesized crystals was about 15 nm.

Crystal structure, vibrational and optic properties of 2-N-methylamino-3-methylpyridine N-oxide - Its X-ray and spectroscopic studies as well as DFT quantum chemical calculations.

The crystal and molecular structure and physicochemical properties of 2--methylamino-3-methylpyridine -oxide (MA3MPO) have been studied. MA3MPO was synthesized from 2-amino-3-methylpyridine by several steps to form colorless crystals suitable for crystallographic analysis. The data reveal that MA3MPO crystallizes in the monoclinic space group 2/.

Phase transition in the extreme: a cubic-to-triclinic symmetry change in dielectrically switchable cyanide perovskites.

Two novel three-dimensional metal-organic compounds of formula FAKM(CN), where M = Co, Fe and FA = formamidinium (CH(NH)), have been found to crystallize in a perovskite-like architecture. They have been investigated by X-ray diffraction, dielectric and spectroscopic methods as a function of temperature in order to determine the interactions in the crystals and the mechanism of phase transitions occurring at ca. 321 K upon heating.

Structural, phonon, magnetic and optical properties of novel perovskite-like frameworks of TriBuMe[M(dca)] (TriBuMe = tributylmethylammonium; dca = dicyanamide; M = Mn, Fe, Co, Ni).

We report the synthesis, crystal structures, thermal, optical and phonon properties of four new metal dicyanamide frameworks templated using tributylmethylammonium cations (TriBuMe). Our results show that these compounds crystallize in a three-dimensional perovskite-like monoclinic structure, space group P2/n, with two inequivalent TriBuMe, one well-ordered and the second one showing distinct disorder. DSC and X-ray diffraction show that TriBuMeMn undergoes an order-disorder structural phase transition near 380 K associated with an increase in the symmetry to the orthorhombic Pnma.

Spectroscopic investigation and DFT modelling studies of Eu complex with 1-(2,6-dihydroxyphenyl)ethanone.

Eu complex with 1-(2,6-dihydroxyphenyl)ethanone in the solid state has been synthesized and characterized by elemental analysis, UV-visible, FT-IR and FT-Raman spectroscopies, powder X-ray diffraction, electron emission under femtosecond laser excitation. The stoichiometry and the formula of the studied complex have been proposed. Its physicochemical properties have been analyzed in terms of the structure and DFT calculations performed for the ligand.

DFT study of electron absorption and emission spectra of pyramidal LnPc(OAc) complexes of some lanthanide ions in the solid state.

The electron absorption and emission spectra were measured for the pyramidal LnPc(OAc) complexes in the solid state and co-doped in silica glass, where Ln=Er, Eu and Ho. The theoretical electron spectra were determined from the quantum chemical DFT calculation using four approximations CAM-B3LYP/LANL2DZ, CAM-B3LYP/CC-PVDZ, B3LYP/LANL2DZ and B3LYP/CC-PVDZ. It was shown that the best agreement between the calculated and experimental structural parameters and spectroscopic data was reached for the CAM-B3LYP/LANL2DZ model.

Alkali metal impact on structural and phonon properties of Er and Tm co-doped MY(WO) (M = Li, Na, K) nanocrystals.

The Pechini and microwave-assisted hydrothermal syntheses of nanocrystalline Er and Tm co-doped MY(WO), where M = Li, Na, K, double tungstates are reported. The obtained samples were characterized using standard X-ray powder diffraction (XRD) technique, Rietveld method, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and IR spectroscopy. The smallest crystallites (about 13 nm) could be obtained for the sodium samples synthesized by both the Pechini (for the resin calcined at 550 °C) and hydrothermal methods (synthesis at 230 °C).

Experimental and theoretical studies of structural phase transition in a novel polar perovskite-like [C2H5NH3][Na0.5Fe0.5(HCOO)3] formate.

We report the synthesis, single crystal X-ray diffraction, and thermal, dielectric, Raman and infrared studies of a novel heterometallic formate [C2H5NH3][Na0.5Fe0.5(HCOO)3] (EtANaFe).

Polarized Raman and IR spectra of oriented Cd(0.9577)Gd(0.0282)□(0.0141)MoO4 and Cd(0.9346)Dy(0.0436)□(0.0218)MoO4 single crystals where □ denotes the cationic vacancies.

Polarized Fourier Transform IR and Raman spectra of Cd0.9577Gd0.0282□0.

Synthesis and order-disorder transition in a novel metal formate framework of [(CH₃)₂NH₂]Na(0.5)Fe(0.5)(HCOO)₃].

We report the synthesis, crystal structure, thermal, dielectric, Raman, infrared, and magnetic properties of [(CH3)2NH2][Na(0.5)Fe(0.5)(HCOO)3] (DMNaFe), the first metal formate framework templated by organic cations, presenting an ABO3 perovskite architecture with NaO6 octahedra as building blocks of the framework.

Temperature-dependent Raman scattering study of cation-deficient Aurivillius phases: Bi2WO6 and Bi2W2O9.

Temperature-dependent Raman scattering experiments were performed on Bi(2)WO(6) and Bi(2)W(2)O(9). Significant changes in the phonon properties of Bi(2)WO(6) were observed as the temperature was increased due to decreased distortion from the B2cb structure. It was shown that instability of the 57 cm(-1) mode that behaved as a soft mode under pressure is not responsible for the Pca2(1) to B2cb phase transition taking place in Bi(2)WO(6) at 933 K.

A Raman scattering study of pressure-induced phase transitions in nanocrystalline Bi₂MoO₆.

Lattice dynamics calculations and a high-pressure Raman scattering study of nanocrystalline Bi(2)MoO(6), a member of the bismuth-layered Aurivillius family of ferroelectrics, are presented. These studies showed the onset of two reversible second-order or weakly first-order phase transitions near 2.5 and 4.

Luminescence and phonon properties of nanocrystalline Bi2WO6:Eu3+ photocatalyst prepared from amorphous precursor.

Bi2WO6:Eu3+ samples were prepared by mechanically activated metathesis reaction and subsequent annealing at different temperatures of the as-prepared precursor. X-ray, TEM, Raman, IR, diffuse reflectance and luminescence studies of the prepared samples are presented. It was found that variation of the particle size have significant impact on phonon and emission properties of this material.

Structural and optical properties of nano-sized K3Nd(PO4)2:Yb3+ orthophosphate.

Nanocrystals of tripotassium neodymium bis-phosphate(V) doped with ytterbium ions, K3Nd(PO4)2: Yb3+, were synthesized by Pechini method. The obtained grains, having an average size of about 40 nm, were characterised by X-ray, electron microscopic, electron absorption, luminescence and IR studies. Moreover, fluorescence decay studies were carried out at room temperature.