Synthesis, temperature-dependent X-ray diffraction and Raman spectroscopic characterization of the sodalite to nosean phase-transformation of |Na 7.7(1) (MnO 4 ) 1.7(2) (H 2 O) 0.8(2) |[AlSiO 4 ] 6

2017 ◽  
Vol 242 ◽  
pp. 144-151 ◽  
Author(s):  
Hilke Petersen ◽  
Lars Robben ◽  
Malik Šehović ◽  
Thorsten M. Gesing
Keyword(s):  
Phase Transformation ◽  
Spectroscopic Characterization ◽  
Synthesis Temperature ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray ◽  
Raman Spectroscopic

Micro-Raman Spectroscopic Characterization of Nanosized TiO2 Powders Prepared by Vapor Hydrolysis

1998 ◽  
Vol 13 (9) ◽  
pp. 2602-2609 ◽  
Author(s):  
Yun-Hong Zhang ◽  
Chak K. Chan ◽  
John F. Porter ◽  
Wei Guo
Keyword(s):  
Spectroscopic Characterization ◽  
Spatial Inhomogeneity ◽  
Titanium Tetraisopropoxide ◽  
X Ray Diffraction ◽  
Raman Analysis ◽  
X Ray ◽  
Raman Spectroscopic ◽  
Hydrolysis Of ◽  
Nanosized Tio2

Micro-Raman analysis was used to study the structure of TiO2 powders produced at low (260 °C) and high (600–900 °C) temperatures by vapor hydrolysis of titanium tetraisopropoxide (TTIP). Spatial inhomogeneity was discovered after the amorphous TiO2 powders produced at low temperature were calcined at 700, 800, and 900 °C for 3 h. The TiO2 powders produced at high temperatures (from 600 to 900 °C) were found to be spatially homogeneous and predominately anatase in structure. Small amounts of rutile and brookite are found for powders produced at 700, 800, and 900 °C after calcination at 600 °C for 3 h. The rutile and brookite impurities are believed to be concentrated on the surface of anatase based on a comparison of results of Raman and x-ray diffraction studies.

scholarly journals 151Eu Mössbauer Spectroscopic Characterization of EuRu4B4 and the New Boride EuRuB4

2010 ◽  
Vol 65 (1) ◽  
pp. 90-94 ◽  
Author(s):  
Thomas Harmening ◽  
Rainer Pöttgen
Keyword(s):  
Boron Atom ◽  
Mössbauer Spectra ◽  
Induction Furnace ◽  
Spectroscopic Characterization ◽  
Two Dimensional ◽  
Temperature Dependent ◽  
X Ray ◽  
Trivalent Europium ◽  
Mossbauer Spectra

Samples of EuRu4B4 and of the new boride EuRuB4 were prepared from europium, RuB, and RuB4 precursor alloys, respectively, in sealed tantalum tubes in an induction furnace. EuRu4B4 crystallizes with the LuRu4B4 structure, a = 748.1(1), c = 1502.3(4) pm. The structure of EuRuB4 was refined on the basis of X-ray diffractometer data: Pbam, a = 599.7(1), b = 1160.7(3), c = 358.06(7) pm, wR2 = 0.0691, 474 F2 values, and 38 variables. The four crystallographically independent boron sites build up layers which consist of almost regular pentagons and heptagons which sandwich the ruthenium and europium atoms, respectively. Within the two-dimensional [B4] networks each boron atom has a slightly distorted trigonal-planar boron coordination with B-B distances in the range 172 - 186 pm. Temperature-dependent 151Eu Mössbauer spectra show stable trivalent europium for EuRu4B4 and EuRuB4

scholarly journals Synthesis and Characterization of K-Ta Mixed Oxides for Hydrogen Generation in Photocatalysis

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Beata Zielińska ◽  
Ewa Mijowska ◽  
Ryszard J. Kalenczuk
Keyword(s):  
Diffuse Reflectance ◽  
Hydrogen Generation ◽  
Mixed Oxides ◽  
X Ray Diffraction ◽  
X Ray ◽  
Raman Spectroscopic ◽  
Photocatalytic Hydrogen Generation ◽  
Irregular Structure ◽  
Transmission Electron

K-Ta mixed oxides photocatalysts have been prepared by impregnation followed by calcination. The influence of the reaction temperature (450°C–900°C) on the phase formation, crystal morphology, and photocatalytic activity in hydrogen generation of the produced materials was investigated. The detailed analysis has revealed that all products exhibit high crystallinity and irregular structure. Moreover, two different crystal structures of potassium tantalates such as KTaO3and K2Ta4O11were obtained. It was also found that the sample composed of KTaO3and traces of unreacted Ta2O5(annealed at 600°C) exhibits the highest activity in the reaction of photocatalytic hydrogen generation. The crystallographic phases, optical and vibronic properties were examined by X-ray diffraction (XRD) and diffuse reflectance (DR) UV-vis and resonance Raman spectroscopic methods, respectively. Morphology and chemical composition of the produced samples were studied using a high-resolution transmission electron microscope (HR-TEM) and an energy dispersive X-ray spectrometer (EDX) as its mode.

Gallium-containing Heusler phases ScRh2Ga, ScPd2Ga, TmRh2Ga and LuRh2Ga – magnetic and solid state NMR-spectroscopic characterization

2017 ◽  
Vol 72 (8) ◽  
pp. 609-615
Author(s):  
Lukas Heletta ◽  
Stefan Seidel ◽  
Christopher Benndorf ◽  
Hellmut Eckert ◽  
Rainer Pöttgen
Keyword(s):  
Solid State ◽  
Solid State Nmr ◽  
Spectroscopic Characterization ◽  
Structural Disorder ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
Phase Purity ◽  
X Ray ◽  
Arc Melting ◽  
Pauli Paramagnetism

AbstractThe gallium-containing Heusler phases ScRh2Ga, ScPd2Ga, TmRh2Ga and LuRh2Ga have been synthesized by arc-melting of the elements followed by different annealing sequences to improve phase purity. The samples have been studied by powder X-ray diffraction. The structures of Lu0.97Rh2Ga1.03 (Fm3̅m, a=632.94(5) pm, wR2=0.0590, 46 F2 values, seven variables) and Sc0.88Rh2Ga1.12 (a=618.91(4) pm, wR2=0.0284, 44 F2 values, six variables) have been refined from single crystal X-ray diffractometer data. Both gallides show structural disorder through Lu/Ga and Sc/Ga mixing. Temperature dependent magnetic susceptibility measurements showed Pauli paramagnetism for ScRh2Ga, ScPd2Ga, and LuRh2Ga and Curie-Weiss paramagnetism for TmRh2Ga. 45Sc and 71Ga solid state MAS NMR spectroscopic investigations of the Sc containing compounds confirmed the site mixing effects typically observed for Heusler phases. The data indicate that the effect of mixed Sc/Ga occupancy is significantly stronger in ScRh2Ga than in ScPd2Ga.

scholarly journals PECHINI SYNTHESIS AND CHARACTERIZATION OF Eu3+ DOPED ZnCo2O4 SPINELS

2005 ◽  
Vol 03 (2) ◽  
pp. 24-29
Author(s):  
P.M. PIMENTEL ◽  
A.M.G. PEDROSA ◽  
H.K.S. SOUZA ◽  
C.N.S. JÚNIOR ◽  
R.C.A. PINTO ◽  
...  
Keyword(s):  
Spinel Structure ◽  
Pechini Method ◽  
Synthesis Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Spinel Oxides ◽  
Diffraction Patterns ◽  
Pechini Synthesis ◽  
Spinel Structures

Spinel oxides with the composition ZnCo2O4 and ZnCo2O4:Eu3+ have been synthesized by the Pechini method and characterized by X-ray diffraction, infrared spectroscopy, thermal analysis and scanning electron microscopy. IR spectroscopy revealed the presence of n1 and n2 bands, typical of spinel structures. The formation of monophase cubic spinel structure was confirmed by X-ray diffraction patterns. Extra lines corresponding to other phase has been observed in the powders calcined at 900 ºC. The results showed the extremely lower synthesis temperature than those presents in conventional methods.

scholarly journals Synthesis, Crystal Structures, and Spectroscopic Characterization of Bis-aldehyde Monomers and Their Electrically Conductive Pristine Polyazomethines

Polymers ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1498 ◽  
Author(s):  
Abdul Hafeez ◽  
Zareen Akhter ◽  
John F. Gallagher ◽  
Nawazish Ali Khan ◽  
Asghari Gul ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Spectroscopic Characterization ◽  
Spectroscopic Techniques ◽  
Conductivity Measurements ◽  
X Ray Diffraction ◽  
Electrically Conductive ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Ft Ir

Bis-aldehyde monomers 4-(4′-formyl-phenoxy)benzaldehyde (3a), 3-methoxy-4-(4′-formyl-phenoxy)benzaldehyde (3b), and 3-ethoxy-4-(4′-formyl-phenoxy)benzaldehyde (3c) were synthesized by etherification of 4-fluorobenzaldehyde (1) with 4-hydroxybenzaldehyde (2a), 3-methoxy-4-hydroxybenzaldehyde (2b), and 3-ethoxy-4-hydroxybenzaldehyde (2c), respectively. Each monomer was polymerized with p-phenylenediamine and 4,4′-diaminodiphenyl ether to yield six poly(azomethine)s. Single crystal X-ray diffraction structures of 3b and 3c were determined. The structural characterization of the monomers and poly(azomethine)s was performed by FT-IR and NMR spectroscopic techniques and elemental analysis. Physicochemical properties of polymers were investigated by powder X-ray diffraction, thermogravimetric analysis (TGA), viscometry, UV–vis, spectroscopy and photoluminescence. These polymers were subjected to electrical conductivity measurements by the four-probe method, and their conductivities were found to be in the range 4.0 × 10−5 to 6.4 × 10−5 Scm−1, which was significantly higher than the values reported so far.

Structural and IR-spectroscopic characterization of magnesium acesulfamate

2016 ◽  
Vol 71 (1) ◽  
pp. 51-55 ◽  
Author(s):  
Oscar E. Piro ◽  
Gustavo A. Echeverría ◽  
Beatriz S. Parajón-Costa ◽  
Enrique J. Baran
Keyword(s):  
Crystal Structure ◽  
Aqueous Solution ◽  
Elemental Analysis ◽  
Spectroscopic Characterization ◽  
Magnesium Carbonate ◽  
X Ray Diffraction ◽  
Triclinic Space Group ◽  
X Ray ◽  
Ir Spectroscopic

AbstractMagnesium acesulfamate, Mg(C4H4NO4S)2·6H2O, was prepared by the reaction of acesulfamic acid and magnesium carbonate in aqueous solution, and characterized by elemental analysis. Its crystal structure was determined by single crystal X-ray diffraction methods. The substance crystallizes in the triclinic space group P1̅ with one molecule per unit cell. The FTIR spectrum of the compound was also recorded and is briefly discussed. Some comparisons with other simple acesulfamate and saccharinate salts are also made.

Synthesis and Characterization of Tetrakis(pentafluoroethyl)germane

Synthesis ◽  
2017 ◽  
Vol 49 (11) ◽  
pp. 2389-2393 ◽  
Author(s):  
Stefanie Pelzer ◽  
Beate Neumann ◽  
Hans-Georg Stammler ◽  
Nikolai Ignat’ev ◽  
Reint Eujen ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
Ir Spectroscopy ◽  
Diffraction Analysis ◽  
Spectroscopic Characterization ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Comprehensive Characterization

This paper describes the synthesis and comprehensive characterization of tetrakis(pentafluoroethyl)germane. In addition to a complete NMR spectroscopic characterization, including the rarely used 73Ge NMR spectroscopy, Ge(C2F5)4 was studied by IR spectroscopy, mass spectrometry as well as X-ray diffraction analysis. A 73Ge NMR investigation as well as an X-ray diffraction study of the related germane Ge(CF3)4 are also included.

Crystallographic and spectroscopic characterization of a natural Zn-rich spinel approaching the endmember gahnite (ZnAl2O4) composition

2013 ◽  
Vol 77 (7) ◽  
pp. 2941-2953 ◽  
Author(s):  
V. D’Ippolito ◽  
G. B. Andreozzi ◽  
F. Bosi ◽  
U. Hålenius ◽  
L. Mantovani ◽  
...  
Keyword(s):  
Optical Absorption ◽  
Spectroscopic Characterization ◽  
Structural Formula ◽  
Unit Cell Dimension ◽  
X Ray Diffraction ◽  
Crystal Chemical Analysis ◽  
X Ray ◽  
Intervalence Charge Transfer ◽  
Oxide Spinel

AbstractThe crystal chemistry of a natural, gem-quality, blue-grey Zn-rich spinel crystal from Jemaa, Kaduna State, Nigeria, was studied using electron microprobe, single-crystal X-ray diffraction, optical absorption and Raman spectroscopies. The composition of the crystal approaches the gahnite endmember (ZnAl2O4), ∼94 mol.%, with the remainder being dominated by a hercynite component (FeAl2O4). The unit-cell dimension is 8.0850(3) Å and the tetrahedral and octahedral bond distances are determined as T–O 1.9485(6) Å and M–O 1.9137(3) Å. Crystal chemical analysis resulted in the empirical structural formula T(Zn0.94Fe2+0.03Al0.03)M (Al1.96Fe2+0.03Fe3+0.01)O4, which shows Zn and Al almost fully ordered in the tetrahedrally and octahedrally coordinated T and M sites, respectively. Raman spectra obtained using the excitation of the blue 473.1 nm line of a Nd:YAG laser display three of the five Raman-active modes predicted for the general oxide spinel group of minerals. These are the Eg mode at 420.6 cm–1 and the T2g modes at 510 cm–1 and 661 cm–1, due to vibrations in the AlO6 octahedra. Optical absorption spectra recorded in the UV/VIS-NIR-MIR range 2000 29000 cm–1 show a dominant absorption band at ∼5000 cm–1 which is caused by spin-allowed electronic d–d transitions in Fe2+ located at the T sites. The blue-grey hue exhibited by the sample is mainly due to spin-forbidden electronic transitions in TFe2+ and to MFe2+ ↔MFe3+ intervalence charge transfer, and the poor saturation of the colour is due to the small concentration of Fe2+ and Fe3+.

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