Intraionic Structure of HS04- and Alkali Cation Configuration in Molten NaHS04 and KHS04

1994 ◽  
Vol 49 (7-8) ◽  
pp. 785-789 ◽  
Author(s):  
K. Fukushima ◽  
M. Murofushi ◽  
M . Oki ◽  
K. Igarashi ◽  
J. Mochinaga ◽  
...  
Keyword(s):  
Molten Salts ◽  
Molecular Orbital Calculations ◽  
Distorted Tetrahedron ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bond Lengths ◽  
Semi Empirical ◽  
Polyatomic Anion ◽  
Short Range Structure

Abstract The short range structure of molten NaHSO4(I) and KHSO4(II) was estimated by X-ray diffraction. The polyatomic anion, HSO4-, in both molten salts was found to have a distorted tetrahedral structure in which the bond lengths of S-O and S-OH were 1.45 Å and 1.53 Å in (I) and 1.46 Å and 1.56 Å in (II), respectively. The coordination number of the Na+ or K+ around the HSO4- was evaluated to be about unity. The semi-empirical molecular orbital calculations by the MNDO-MOPAC method were applied to the determination of the intraionic structure of the H S 0 4 and the bond lengths of S-O and S -OH were computed to be 1.528 Å and 1.666 Å, respectively, supporting qualitatively that the HSO4- forms a rather distorted tetrahedron.

Mangan(II)-Komplexe mit dem vierzähnigen Stickstoffliganden C12H22N6(L): Synthese von [MnX2L] (X = Cl, Br, I, NCS), Kristallstrukturen von [MnCl2L] und [MnBr2L] / Manganese(II) Complexes with the Tetradentate Nitrogen Ligand C12H22N6(L): Synthesis of [MnX2L] (Χ = Cl, Br, I, NCS), Crystal Structures of [MnCl2L] and [MnBr2L]

1989 ◽  
Vol 44 (6) ◽  
pp. 632-636 ◽  
Author(s):  
Peter Stolz ◽  
Wolfgang Saak ◽  
Henry Strasdeit ◽  
Siegfried Pohl
Keyword(s):  
Single Crystal ◽  
Diffraction Data ◽  
Tetradentate Ligand ◽  
Distorted Tetrahedron ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Reaction Conditions ◽  
X Ray ◽  
Nitrogen Ligand ◽  
Bond Lengths

[MnCl2(C12H22N6)] (1) and [MnBr2(C12H22N6)] (2) are obtained from the reaction of MnX2 (X = Cl, Br) with C12H22N6 in methanolic solution.In chloroform MnI2, OPPh3, and C12H22N6 react to give [MnI2(C12H22N6)] (3). With small variations of the reaction conditions [MnI2(C12H22N6)] · xCHCl3 (4) may be crystallized. The reaction of [Mn(NCS)2(OPPh3)4] with C12H22N6 in CHCl3 solution gives [Mn(NCS)2(C12H22N6)] · xCHCl3 (5). The structures of 1 and 2 were determined from single crystal X-ray diffraction data. The isotypic compounds crystallize in the orthorhombic space group Pbcn with Z = 4; 1: a = 1592.4(1), b = 785.0(1), c = 1270.7(1) pm; 2: a = 1590.0(1), b = 802.6(1), c = 1316.6(1) pm. C12H22N6 acts as a tetradentate ligand. The isolated complexes exhibit a twofold symmetry.Manganese(II) is in a six-coordinate environment, which can be described better as a distorted tetrahedron with two additional Mn-N bonds rather than as a distorted octahedron.The Mn-N bond lengths are 229.9(1) and 248.7(1) pm for 1 and 228.2(3) and 248.4(3) pm for 2. The Mn-Hal bond lengths are 239.2(1) (1) and 254.2(1) pm (2)

Les liaisons phosphore-azote via l'étude cristalline et moléculaire d'un iminodiazaphospholane

1984 ◽  
Vol 62 (11) ◽  
pp. 2186-2191 ◽  
Author(s):  
Marie-Rose Marre ◽  
Michel Sanchez ◽  
Robert Wolf ◽  
Joël Jaud ◽  
Jean Galy
Keyword(s):  
Nitrogen Atom ◽  
Single Crystal ◽  
Lone Pair ◽  
Empirical Method ◽  
Distorted Tetrahedron ◽  
X Ray Diffraction ◽  
Parallel Orientation ◽  
X Ray ◽  
Bond Lengths ◽  
Exocyclic Nitrogen Atom

Iminodiazophospholane 1 was obtained as monoclinic crystals, space group P21/c with a = 10.243(9), b = 17.236(5), c = 11.992(9) Å, and Z = 4. The structure was determined by single-crystal X-ray diffraction and was refined up to R = 0.056[Formula: see text]for 1342 reflections. The geometry of the molecule is that of a distorted tetrahedron with [Formula: see text] angles varying from 91.8° (ring angle) to 121.7° for [Formula: see text]. The diazophospholane ring has an envelope conformation where one of the 2 carbon atoms is at the tip. The three tricoordinated nitrogen atoms have a planar structure; the lone pairs on the two ring nitrogens have parallel orientation and both are orthogonal to the lone pair of the exocyclic nitrogen atom (N7). The P—N bond lengths are relatively short, falling between 1.620 Å and 1.669 Å, while the P2=N6 bond of 1.539 Å is among the smallest values ever reported. The multiplicities of the P—N bonds were assigned on the basis of an empirical method: 0.10 for the two cyclic P—N, 0.25 for the exocyclic P—N, and 0.60 for [Formula: see text] [Journal translation]

Sem and X-Ray Analysis of Renal and Biliary Calculi

1976 ◽  
Vol 34 ◽  
pp. 306-307
Author(s):  
R. J. Narconis ◽  
G. L. Johnson
Keyword(s):  
Chemical Constituents ◽  
Natural State ◽  
X Ray Diffraction ◽  
Chemical Methods ◽  
X Ray ◽  
Additional Dimension ◽  
Biliary Calculi ◽  
Calculus Formation ◽  
Scanning Electron

Analysis of the constituents of renal and biliary calculi may be of help in the management of patients with calculous disease. Several methods of analysis are available for identifying these constituents. Most common are chemical methods, optical crystallography, x-ray diffraction, and infrared spectroscopy. The application of a SEM with x-ray analysis capabilities should be considered as an additional alternative.A scanning electron microscope equipped with an x-ray “mapping” attachment offers an additional dimension in its ability to locate elemental constituents geographically, and thus, provide a clue in determination of possible metabolic etiology in calculus formation. The ability of this method to give an undisturbed view of adjacent layers of elements in their natural state is of advantage in determining the sequence of formation of subsequent layers of chemical constituents.

New Coordination Compounds of Fe(III) with Organic Ligands

2009 ◽  
Vol 59 (12) ◽  
Author(s):  
Mihaela Flondor ◽  
Ioan Rosca ◽  
Doina Sibiescu ◽  
Mihaela-Aurelia Vizitiu ◽  
Daniel-Mircea Sutiman ◽  
...  
Keyword(s):  
Chemical Analysis ◽  
Complex Compounds ◽  
Organic Ligands ◽  
X Ray Diffraction ◽  
X Ray ◽  
Elemental Chemical Analysis ◽  
Structural Formulae ◽  
Paramagnetic Properties

In this paper the synthesis and the study of some complex compounds of Fe(III) with ligands derived from: 2-(4-chloro-phenylsulfanyl)-1-(2-hydroxy-3,5-diiodo-phenyl)-ethanone (HL1), 1-(3,5-dibromo-2-hydroxy-phenyl)-2-phenylsulfanyl-ethanone(HL2), and 2-(4-chloro-phenylsulfanyl)-1-(3,5-dibromo-2-hydroxy-phenyl)-ethanone (HL3) is presented. The characterization of these complexes is based on method as: the elemental chemical analysis, IR and ESR spectroscopy, M�ssbauer, the thermogravimetric analysis and X-ray diffraction. Study of the IR and chemical analysis has evidenced that the precipitates form are a complexes and the combination ratio of M:L is 1:2. The central atoms of Fe(III) presented paramagnetic properties and a octaedric hybridization. Starting from this precipitation reactions, a method for the gravimetric determination of Fe(III) with this organic ligands has been possible. Based on the experimental data on literature indications, the structural formulae of the complex compounds are assigned.

Crystal structure determination of the conformation of two bicyclo[3.3.1]nonan-ones

1985 ◽  
Vol 63 (6) ◽  
pp. 1166-1169 ◽  
Author(s):  
John F. Richardson ◽  
Ted S. Sorensen
Keyword(s):  
Crystal Structure ◽  
Direct Methods ◽  
Chair Conformation ◽  
Molecular Structures ◽  
Boat Conformation ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Final Agreement

The molecular structures of exo-7-methylbicyclo[3.3.1]nonan-3-one, 3, and the endo-7-methyl isomer, 4, have been determined using X-ray-diffraction techniques. Compound 3 crystallizes in the space group [Formula: see text] with a = 15.115(1), c = 7.677(2) Å, and Z = 8 while 4 crystallizes in the space group P21 with a = 6.446(1), b = 7.831(1), c = 8.414(2) Å, β = 94.42(2)°, and Z = 2. The structures were solved by direct methods and refined to final agreement factors of R = 0.041 and R = 0.034 for 3 and 4 respectively. Compound 3 exists in a chair–chair conformation and there is no significant flattening of the chair rings. However, in 4, the non-ketone ring is forced into a boat conformation. These results are significant in interpreting what conformations may be present in the related sp2-hybridized carbocations.

scholarly journals Mining Wastes of an Albite Deposit as Raw Materials for Vitrified Mullite Ceramics

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 232
Author(s):  
Pedro J. Sánchez-Soto ◽  
Eduardo Garzón ◽  
Luis Pérez-Villarejo ◽  
George N. Angelopoulos ◽  
Dolores Eliche-Quesada
Keyword(s):  
Particle Size ◽  
Raw Materials ◽  
Phase Evolution ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Mining Wastes ◽  
X Ray Diffraction ◽  
X Ray ◽  
Maximum Value

In this work, an examination of mining wastes of an albite deposit in south Spain was carried out using X-ray Fluorescence (XRF), X-ray diffraction (XRD), particle size analysis, thermo-dilatometry and Differential Thermal Analysis (DTA) and Thermogravimetric (TG) analysis, followed by the determination of the main ceramic properties. The albite content in two selected samples was high (65–40 wt. %), accompanied by quartz (25–40 wt. %) and other minor minerals identified by XRD, mainly kaolinite, in agreement with the high content of silica and alumina determined by XRF. The content of Na2O was in the range 5.44–3.09 wt. %, being associated with albite. The iron content was very low (<0.75 wt. %). The kaolinite content in the waste was estimated from ~8 to 32 wt. %. The particle size analysis indicated values of 11–31 wt. % of particles <63 µm. The ceramic properties of fired samples (1000–1350 °C) showed progressive shrinkage by the thermal effect, with water absorption and open porosity almost at zero at 1200–1250 °C. At 1200 °C, the bulk density reached a maximum value of 2.38 g/cm3. An abrupt change in the phase evolution by XRD was found from 1150 to 1200 °C, with the disappearance of albite by melting in accordance with the predictions of the phase diagram SiO2-Al2O3-Na2O and the system albite-quartz. These fired materials contained as main crystalline phases quartz and mullite. Quartz was present in the raw samples and mullite was formed by decomposition of kaolinite. The observation of mullite forming needle-shape crystals was revealed by Scanning Electron Microscopy (SEM). The formation of fully densified and vitrified mullite materials by firing treatments was demonstrated.

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