Étude comparative dans la série des dibenzamido-alcanes, composés modèles des poly(oligométhylènes téréphtalamides)

1985 ◽  
Vol 63 (12) ◽  
pp. 3390-3397 ◽  
Author(s):  
Josée Brisson ◽  
François Brisse
Keyword(s):  
Raman Spectroscopy ◽  
Aromatic Ring ◽  
Torsion Angle ◽  
Amide Group ◽  
Aliphatic Chain ◽  
X Ray Diffraction ◽  
X Ray ◽  
V Band ◽  
Infrared And Raman Spectroscopy ◽  
Ir And Raman

The dibenzamido alcanes, nDBN, for n = 2–10, have been synthesized and characterized by X-ray diffraction and infrared and Raman spectroscopy. From X-ray diffraction it was observed than the dihedral angle ε between the aromatic ring and the amido group averaged 28.3° and did not vary significantly with n. The torsion angle τ between the amide group and the aliphatic chain was found to be near 180° for n = 4, 6, 8, and 10. However, for n = 2, 3, 5, and 7, τ averaged 98°. In this last case the plane of the aliphatic chain is nearly perpendicular to the plane of the amide group. The study of ir and Raman spectra in relation to conformation revealed that the position of the amide V band depends on the value of the τ angle and could be used to infer if the latter is close to 180° or not.

Refinement of the layered titanosilicate AM-1 from single-crystal X-ray diffraction data

2007 ◽  
Vol 63 (11) ◽  
pp. i186-i186 ◽  
Author(s):  
Stanislav Ferdov ◽  
Uwe Kolitsch ◽  
Christian Lengauer ◽  
Ekkehart Tillmanns ◽  
Zhi Lin ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Hydrogen Bonding ◽  
Single Crystal ◽  
Single Crystals ◽  
Diffraction Data ◽  
X Ray Diffraction ◽  
X Ray ◽  
First Time ◽  
Ir And Raman ◽  
Bonding Scheme

The structure of the layered noncentrosymmetric titanosilicate AM-1 (also known as JDF-L1, disodium titanium tetrasilicate dihydrate), Na4Ti2Si8O22·4H2O, grown as small single crystals without the use of organics, has been refined from single-crystal X-ray diffraction data. The H atom has been located for the first time, and the hydrogen-bonding scheme is also characterized by IR and Raman spectroscopy. All atoms are in general positions except for the Na, the Ti, one Ti-bound O, one Si-bound O and the water O atoms (site symmetries 2, 4, 4, 2 and 2, respectively).

The effect of coordinated water on the connectivity of uranium(IV) sulfatex-hydrate: [U(SO4)2(H2O)5]·H2O and [U(SO4)2(H2O)6]·2H2O, and a comparison with other known structures

2014 ◽  
Vol 70 (7) ◽  
pp. 726-731 ◽  
Author(s):  
Alexander D. Burns ◽  
Brian O. Patrick ◽  
Anita E. Lam ◽  
David Dreisinger
Keyword(s):  
Raman Spectroscopy ◽  
Binding Mode ◽  
Three Dimensions ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
X Ray ◽  
Anhydrous Compound ◽  
Coordinated Water ◽  
Ir And Raman ◽  
Sulfate Complexes

Two new solid-state uranium(IV) sulfatex-hydrate complexes (wherexis the total number of coordinated plus solvent waters), namelycatena-poly[[pentaaquauranium(IV)]-di-μ-sulfato-κ4O:O′] monohydrate], {[U(SO4)2(H2O)5]·H2O}n, and hexaaquabis(sulfato-κ2O,O′)uranium(IV) dihydrate, [U(SO4)2(H2O)6]·2H2O, have been synthesized, structurally characterized by single-crystal X-ray diffraction and analyzed by vibrational (IR and Raman) spectroscopy. By comparing these structures with those of four other known uranium(IV) sulfatex-hydrates, the effect of additional coordinated water molecules on their structures has been elucidated. As the number of coordinated water molecules increases, the sulfate bonds are displaced, thus changing the binding mode of the sulfate ligands to the uranium centre. As a result, uranium(IV) sulfatex-hydrate changes from being fully crosslinked in three dimensions in the anhydrous compound, through sheet and chain linking in the tetra- and hexahydrates, to fully unlinked molecules in the octa- and nonahydrates. It can be concluded that coordinated waters play an important role in determining the structure and connectivity of UIVsulfate complexes.

scholarly journals Chlorosubstituted Copper Phthalocyanines: Spectral Study and Structure of Thin Films

Molecules ◽  
2020 ◽  
Vol 25 (7) ◽  
pp. 1620 ◽  
Author(s):  
Alexandr Sukhikh ◽  
Dmitry Bonegardt ◽  
Darya Klyamer ◽  
Pavel Krasnov ◽  
Tamara Basova
Keyword(s):  
Thin Films ◽  
Raman Spectroscopy ◽  
Substrate Surface ◽  
X Ray Diffraction ◽  
Amorphous Films ◽  
X Ray ◽  
Disordered Films ◽  
Copper Phthalocyanines ◽  
First Time ◽  
Ir And Raman

In this work, the tetra-, octa- and hexadecachloro-substituted copper phthalocyanines CuPcClx (where x can equal 4, 8 or 16) were investigated by the methods of vibrational (IR and Raman) spectroscopy and X-ray diffraction. The assignment of the most intense bands, both in IR and Raman spectra, was carried out on the basis of DFT calculations. The structure of a CuPcCl4 single crystal grown by sublimation in vacuum was refined for the first time. The effect of chloro-substitution on the structure of CuPcClx thin films deposited in a vacuum onto a glass substrate at 50 and 200 °C was studied. It was shown that CuPcCl4 formed polycrystalline films with the preferential orientation of the (100) crystallographic plane of crystallites parallel to the substrate surface when deposited on a substrate at 50 °C. Introduction of more Cl-substituents into the phthalocyanine macrocycle leads to the formation of amorphous films on the substrates at 50 °C. At the elevated substrate temperature, the growth of polycrystalline disordered films was observed for all three copper phthalocyanines.

scholarly journals Biogenic Orthorhombic α-Calcium Formate from Sediments of Alkali Lake, Oregon, USA

Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 448
Author(s):  
Nikita V. Chukanov ◽  
Cesar Menor-Salvan ◽  
Vladislav V. Gurzhiy ◽  
Alina R. Izatulina ◽  
Igor V. Pekov ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Diffraction Analysis ◽  
Anthropogenic Pollution ◽  
Agent Orange ◽  
Low Density ◽  
X Ray Diffraction ◽  
X Ray ◽  
Infrared And Raman Spectroscopy ◽  
Two Factors ◽  
Calcium Formate

Centimeter-sized crystals of orthorhombic calcium formate, α-Ca(HCO2)2 from Alkali Lake, Oregon, USA have been studied by means of powder and single-crystal X-ray diffraction analysis, infrared, and Raman spectroscopy. Based on the data on carbon isotope abundance in calcium formate and associated minerals, it was concluded that the formation of α-Ca(HCO2)2 may be a result of a combination of two factors: lake microbial metabolism and anthropogenic pollution with Agent Orange. Possible causes of stability of the low-density tetragonal β-Ca(HCO2)2 polymorph (formicaite) in boron ores are discussed.

Behavior of beryllium halides and triflate in acetonitrile solutions

2020 ◽  
Vol 75 (11) ◽  
pp. 939-949
Author(s):  
Nils Spang ◽  
Matthias Müller ◽  
William Augustinov ◽  
Magnus R. Buchner
Keyword(s):  
Raman Spectroscopy ◽  
Solid State ◽  
Dominant Species ◽  
State Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Halide Complexes ◽  
Acetonitrile Solutions ◽  
Dinuclear Compounds ◽  
Ir And Raman

AbstractThe solution behavior of beryllium halides and triflate in acetonitrile was studied by NMR, IR and Raman spectroscopy. Thereby mononuclear units [(MeCN)2BeX2] (X = Cl, Br, I, OTf) were identified as dominant species in these solutions. The solid state structure of [(MeCN)2Be(OTf)2] has been determined by X-ray diffraction. If only one equivalent of MeCN is used the dinuclear compounds [(MeCN)BeX2]2 (X = Cl, Br, I) are formed. Partial halide and triflate dissociation into the monomeric complexes as well as the formation of hetero-halide complexes [(MeCN)2BeClBr], [(MeCN)2BeClI] and [(MeCN)2BeBrI] was observed.

Synthesis, structure, and vibrational spectrum of poly-μ-pyrazine(pyrazine)(trifluoromethanesulfonato-O)copper(I)

1989 ◽  
Vol 67 (11) ◽  
pp. 1964-1969 ◽  
Author(s):  
T. Otieno ◽  
S. J. Rettig ◽  
R. C. Thompson ◽  
J. Trotter
Keyword(s):  
Crystal Structure ◽  
Raman Spectroscopy ◽  
Copper Ions ◽  
Heavy Atom ◽  
X Ray Diffraction ◽  
Full Matrix ◽  
X Ray ◽  
Methanol Solutions ◽  
Infrared And Raman Spectroscopy ◽  
Spectroscopy Studies

Orange–brown crystals of composition Cu(pyz)2(CF3SO3) (pyz = pyrazine, 1,4-diazine) were obtained from methanol solutions containing Cu(CF3SO3)2 and pyrazine in approximate 1:2 mole ratio. Single crystal X-ray diffraction and infrared and Raman spectroscopy studies are reported. Crystals of the title compound are triclinic, a = 8.312(2), b = 10.903(3), c = 8.201(2) Å, α = 92.53(2), β = 113.77(2), γ = 91.40(2)°, Z = 2, space group [Formula: see text] The structure was solved by heavy atom methods and was refined by full-matrix least-squares to R = 0.035 and Rw = 0.044 for 2458 reflections with 1 ≥ 3σ(I). The compound contains chains of copper ions linked by bidentate bridging pyrazine ligands. The coordination around each copper is completed by monodentate pyrazine and trifluoromethanesulfonato groups to produce a distorted tetrahedral CuN3O chromophore. Keywords: crystal structure, μ-pyrazine copper(I) triflate polymer, vibrational spectra.

scholarly journals High-pressure synthesis and crystal structure of HP-Al2B3O7(OH)

2020 ◽  
Vol 75 (11) ◽  
pp. 975-981
Author(s):  
Daniela Vitzthum ◽  
Ingo Widmann ◽  
Markus Plank ◽  
Bastian Joachim-Mrosko ◽  
Hubert Huppertz
Keyword(s):  
Crystal Structure ◽  
Raman Spectroscopy ◽  
High Pressure ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
Synthesis And Crystal Structure ◽  
X Ray ◽  
High Pressure High Temperature ◽  
Pressure Synthesis ◽  
Ir And Raman

AbstractOrthorhombic HP-Al2B3O7(OH) was synthesized in a Walker-type multianvil apparatus under high-pressure/high-temperature conditions of 12.4 GPa and 1200 °C, respectively. Its structure is isotypic to that of Ga2B3O7(OH) and has been determined via single-crystal X-ray diffraction at room temperature. HP-Al2B3O7(OH) crystallizes in the space group Cmce (Z = 8) with the lattice parameters a = 10.3124(4), b = 7.3313(3), c = 10.4801(5) Å, and V = 792.33(6) Å3. The compound has also been characterized by IR and Raman spectroscopy.

Raman spectroscopy and X-ray diffraction of lithium niobate at temperatures up to 1300○-4.80pt○C

2005 ◽  
Vol 126 ◽  
pp. 101-105 ◽  
Author(s):  
B. Moulin ◽  
L. Hennet ◽  
D. Thiaudière ◽  
P. Melin ◽  
P. Simon
Keyword(s):  
Raman Spectroscopy ◽  
Lithium Niobate ◽  
X Ray Diffraction ◽  
X Ray
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