Physico-Chemical Characterization of Some 5,5-Disubstituted-1,3-Dixanthyl Barbituric Acids

1967 ◽  
Vol 21 (4) ◽  
pp. 225-231 ◽  
Author(s):  
B. C. Flann ◽  
J. A. R. Cloutier
Keyword(s):  
Experimental Data ◽  
Powder Diffraction ◽  
Infrared Spectra ◽  
Chemical Characterization ◽  
Melting Points ◽  
X Ray ◽  
Physico Chemical ◽  
Diffraction Patterns ◽  
Derivatives Of

The dixanthyl derivatives of 21 clinically important barbituric acids have been prepared. Melting points, infrared spectra, and x-ray powder-diffraction patterns of the purified compounds are presented. Infrared evidence is used to discuss the position of the linkage between the xanthyl and barbiturate portions of the derivatives. The experimental data should prove of particular value for the microchemical identification of barbiturates.

Phonons and Crystalline Structure of Hg1−xCdxS e Alloys (0 < x ≤ 0.5)

2012 ◽  
Vol 1372 ◽  
Author(s):  
David A. Miranda ◽  
S. A. López-Rivera ◽  
Ch. Power ◽  
J. A. Henao ◽  
M. A. Macías
Keyword(s):  
Experimental Data ◽  
Raman Spectroscopy ◽  
Powder Diffraction ◽  
Molar Fraction ◽  
Face Centered Cubic ◽  
X Ray ◽  
Cell Parameters ◽  
Cubic Structure ◽  
Diffraction Patterns ◽  
Face Centered

ABSTRACTPhonons and crystalline structures of Hg1−xCdxSe alloys (0 ≤ x ≤ 0.5) were studied by Raman spectroscopy and X-ray powder diffraction patterns at 298K. The crystalline alloys were prepared by a special combination of synthesis and the Bridgman method. Experimental data showed a face-centered cubic structure, $F\overline 4 \,3\,m$ (No. 216), for all samples, exhibiting a linear dependence for Cd molar fraction, x, for cell parameters, a, and the mass densities, ρ. Phonon frequencies were analyzed using the Romevi-Romevi model for phonons in multicomponent alloys, obtaining a fair agreement with experimental data. Furthermore, an algorithm to implement the Romevi-Romevi model is proposed.

The thermal behaviour of an Fe-rich illite

Clay Minerals ◽  
1996 ◽  
Vol 31 (1) ◽  
pp. 45-52 ◽  
Author(s):  
E. Murad ◽  
U. Wagner
Keyword(s):  
Powder Diffraction ◽  
Infrared Spectra ◽  
Room Temperature ◽  
Phase Changes ◽  
X Ray ◽  
Structural Breakdown ◽  
Characteristic Features ◽  
Diffraction Patterns ◽  
Good Agreement ◽  
Subsequent Disappearance

AbstractThe phase changes that took place upon heating an Fe-rich illite (OECD #5) to 1300°C in an oxidizing atmosphere were studied by a variety of mineralogical techniques. Infrared spectra, showing the stepwise dehydroxylation of the illite, showed good agreement with variations in sample colour and Mössbauer spectra. Dehydroxylation did not lead to noticeable variations in X-ray powder diffraction patterns until the structural breakdown of illite and formation of new phases at about 900°C Mössbauer spectroscopy proved to be very sensitive to all changes induced by heating, showing the disappearance of Fe2+ at 250°C, the gradual dehydroxylation between about 350 and 900°C, and characteristic features of the products formed at higher temperatures, e.g. the formation of hematite as the illite structure breaks down and the subsequent disappearance of hematite due to the incorporation of Fe in glass above 1200°C. The formation of hematite in clusters large enough to order magnetically at room temperature was first observed in the sample heated to 900°C, whereas at 4.2 K, significant proportions of a magnetically ordered phase could already be identified in the sample heated to 650°C.

scholarly journals Synthesis and Physico-Chemical Characterization of a New Non-Centrosymmetric Organic Cation Iodate

2011 ◽  
Vol 7 (2) ◽  
pp. 1315-1323 ◽  
Author(s):  
A.C. Dhiab ◽  
W. Smirani Sta ◽  
M. Rzaigui
Keyword(s):  
Organic Cation ◽  
Three Dimensional ◽  
Chemical Characterization ◽  
Halogen Bonds ◽  
Monoclinic System ◽  
X Ray ◽  
Dimensional Network ◽  
Physico Chemical ◽  
Graph Set

The synthesis, crystal structure and physico-chemical characterization are presented for the piperazinium bis iodate dihydrate. An X-ray investigation has shown that this compound crystallizes in a non-centrosymmetric monoclinic system, space group Pc with the lattice parameters: a = 8.969 (2) Å, b = 6.027 (3)  Å, c = 11.958 (2)  Å; V = 612.7 (3)  Å3 and Z = 2. The structure was solved from 3546 independent reflexions with R1 = 0.053 and wR2 = 0.130. I…O halogen bonds [R22(4) graph-set motif] range between 2.770 (4) and 3.108 (1) Å and connect neighboring IO-3 anions with each other so as to create a bi-dimensional layer parallel to the (b,c) plane. These layers are interconnected via N−H…O and C−H…O, to the piperazinium dication to generate a three-dimensional network.

Enclosing the functional properties of pyrazolato-based coordination polymers within a structural frame: the role of laboratory X-ray powder diffraction

2013 ◽  
Vol 28 (S2) ◽  
pp. S106-S125 ◽  
Author(s):  
Simona Galli ◽  
Norberto Masciocchi
Keyword(s):  
Functional Properties ◽  
Powder Diffraction ◽  
Coordination Polymers ◽  
Laboratory Data ◽  
Recent Experience ◽  
Structural Description ◽  
X Ray ◽  
Physico Chemical ◽  
Metal Bonds

Ab initio X-ray powder diffraction structural analyses from laboratory data have been widely employed in the characterization of coordination polymers not affording single crystals of suitable quality to undergo conventional structural determinations. This is particularly true for coordination polymers built upon strong ligand-to-metal bonds, as those formed by anionic, nitrogen-based heterocycles - pyrazolates, imidazolates, pyrimidinolates and more complex moieties derived therefrom. More than one hundred species belonging to this class have been structurally characterized in the last three decades, affording key, otherwise inaccessible stereochemical and supramolecolar features. This contribution summarizes our most recent experience in the XRPD structural characterization of pyrazolato-based coordination polymers, devoting a special consideration to the methodologies and tricks which allowed us to juxtapose the structural description of these materials to their physico-chemical and, above all, functional properties.

Characterization of Carboxylic Acids: Identification of Their Anilide Derivatives by X-ray Diffractometry

1976 ◽  
Vol 30 (2) ◽  
pp. 204-209 ◽  
Author(s):  
Kenneth J. Garska
Keyword(s):  
Mass Spectrometry ◽  
Carboxylic Acid ◽  
Qualitative Analysis ◽  
Carboxylic Acids ◽  
Isomeric Form ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Patterns ◽  
Derivatives Of

In order to extend the data available for the characterization of carboxylic acids, an x-ray diffraction technique has been used for the identification of their anilide derivatives. This technique often makes possible the identification of carboxylic acids that cannot be examined readily by other techniques such as gas chromotography and mass spectrometry. Reference x-ray diffraction patterns have been obtained for the anilide derivatives of 32 carboxylic acids containing up to 18 carbon atoms. Detailed descriptions are given for obtaining and qualitatively using the x-ray diffraction patterns of these anilides. The x-ray diffraction patterns of these anilides are unique; even closely related acids which differ only in isomeric form produce anilide derivatives which exhibit different and characteristic x-ray diffraction patterns. In the qualitative analysis of single or multicomponent carboxylic acid-containing mixtures, this x-ray diffraction technique is used either alone or with infrared spectrometric techniques.

Studies of the phosphorodiamidates of alkali metals

1969 ◽  
Vol 47 (14) ◽  
pp. 2613-2617 ◽  
Author(s):  
Y. N. Sadana
Keyword(s):  
Powder Diffraction ◽  
Infrared Spectra ◽  
Alkali Metals ◽  
Potassium Salts ◽  
X Ray ◽  
Diffraction Patterns ◽  
Sodium And Potassium

Phosphorodiamidates of lithium, rubidium, and cesium have been prepared and characterized. The infrared spectra and the X-ray powder diffraction patterns of these and the previously known sodium and potassium salts have been recorded and discussed.

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