Influence of Molecular Conformation on the Solid State Packing of 1,2-Diglycerides Study of 1,2-Dipalmitin and Some Structural Analogs by Electron Diffraction, X-Ray Diffraction, and Infrared Spectroscopy

Abstract Diffraction studies on natural 1,2-dipalmitin and on analogs, including those based on the configurational isomers of cyclopentane-1,2,3-triol reveal that the 1,2-diglycerides crystallize from solvent with chain methylene packing identical to the monoclinic form of even-chain alkanes. The chains probably are folded back in “hairpin” fashion as found in phospholipid crystal structures. Acyl shifts are observed to occur in the crystalline solid state at room temperature to give the 1,3-diglyceride. Analogs based on the above-mentioned cyclitols show that isomers with adjacent chains trans to the ring (possibly extended chain packing) or with chains cis to the ring (“hair pin”) crystallize readily. Both possibly extended chain configurational isomers have the α-form as well as β′-forms and a β-polymorph. The hairpin isomers each give a β′-polymorph but only the all-cts isomer gives an α-form.

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Structure and electric properties of cerium substituted SrBi1.8Ce0.2Nb2O9 and SrBi1.8Ce0.2Ta2O9 ceramics

Processing and Application of Ceramics ◽

10.2298/pac1603183a ◽

2016 ◽

Vol 10 (3) ◽

pp. 183-188 ◽

Cited By ~ 5

Author(s):

Mohamed Afqir ◽

Amina Tachafine ◽

Didier Fasquelle ◽

Mohamed Elaatmani ◽

Jean-Claude Carru ◽

...

Keyword(s):

Dielectric Constant ◽

Solid State ◽

Room Temperature ◽

Single Phase ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

Lcr Meter ◽

Curie Temperature Tc

SrBi1.8Ce0.2Nb2O9 (SBCN) and SrBi1.8Ce0.2Ta2O9 (SBCT) powders were prepared via solid-state reaction method. X-ray diffraction analysis reveals that the SBCN and SBCT powders have the single phase orthorhom-bic Aurivillius structure at room temperature. The contribution of Raman scattering and FTIR spectroscopy of these samples were relatively smooth and resemble each other. The calcined powders were uniaxially pressed and sintered at 1250?C for 8 h to obtaine dense ceramics. Dielectric constant, loss tangent and AC conductivity of the sintered Ce-doped SrBi2Nb2O9 and SrBi2Ta2O9 ceramics were measured by LCR meter. The Ce-doped SBN (SBCN) ceramics have a higher Curie temperature (TC) and dielectric constant at TC (380?C and ?? ~3510) compared to the Ce-doped SBT (SBCT) ceramics (330?C and ?? ~115) when measured at 100Hz. However, the Ce-doped SBT (SBCT) ceramics have lower conductivity and dielectric loss.

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Synthèse et caractérisation des oxypentafluorouranates(VI) NH4UOF5, KUOF5, RbUOF5 et CsUOF5

Canadian Journal of Chemistry ◽

10.1139/v78-305 ◽

1978 ◽

Vol 56 (14) ◽

pp. 1874-1880 ◽

Cited By ~ 10

Author(s):

Philippe Joubert ◽

Roland Bougon ◽

Bernard Gaudreau

Keyword(s):

Infrared Spectroscopy ◽

Solid State ◽

Alkali Metal ◽

Vibrational Spectroscopy ◽

Uranium Atom ◽

The Other ◽

Metal Fluoride ◽

X Ray Diffraction ◽

X Ray ◽

Raman And Infrared Spectroscopy

The oxypentafluorouranates(VI) MUOF5, where M = NH4, K, Rb, Cs, have been synthetized from reaction of UOF4 with the ammonium or corresponding alkali metal fluoride in liquid SO2. According to X-ray diffraction, Raman and infrared spectroscopy, and from an isomorphism with the corresponding hexafluorouranates(V) MUF6, two different environments around the uranium atom are observed. In CsUOF5 the five fluorine atoms and the oxygen around the uranium result in a pseudo-octahedral surrounding whereas for the other complexes (M = NH4, K, Rb) each uranium is surrounded by eight light atoms forming a dodecahedron. In this structure the dodecahedra are linked together by fluorine atoms to form infinite chains. The UOF5− ion has been characterized by vibrational spectroscopy in the solid state. The proposed assignment, which was made with the assumption of a C4v symmetry of the UOF5− ion, was confirmed by a force constant calculation. From these data and contrary to the values reported for comparable oxypentafluoroanions, the axial fluorine is found to be less ionic than the equatorial ones.

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Crystal structures of the simple monoclinic and orthorhombic polytypes of tripotassium hexacyanoferrate(III)

Australian Journal of Chemistry ◽

10.1071/ch9781195 ◽

1978 ◽

Vol 31 (6) ◽

pp. 1195 ◽

Cited By ~ 21

Author(s):

BN Figgis ◽

BW Skelton ◽

AH White

Keyword(s):

Single Crystal ◽

Crystal Structures ◽

Room Temperature ◽

Potassium Ferricyanide ◽

X Ray Diffraction ◽

X Ray ◽

Monoclinic Form

The room-temperature (295 K) crystal structures of potassium ferricyanide, K3[Fe(CN)6], have been determined for the simplest monoclinic (a reinvestigation) and orthorhombic polytypes by single- crystal X-ray diffraction. The monoclinic form is P21/c, a 7.047(3), b 10.400(3), c 8.384(3) Ǻ, β 107.29(3)°, Z 2. The iron atoms lie on special positions with symmetry 1. In the orthorhombic form, Pnca, a 13.422(6), b 10.396(4), 8.381(4) Ǻ, Z4, the iron atoms now lie on special positions with symmetry 2 (parallel to c). Residuals are 0.036 and 0.048 for 1232 and 855 'observed' reflections respectively.

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A three-dimensional CdIIcoordination framework: poly[di-μ2-aqua-{μ2-1,4-bis[(1H-1,2,4-triazol-1-yl)methyl]benzene-κ2N4:N4′}di-μ3-terephthalato-κ3O:O′:O′′-dicadmium(II)]

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229614020610 ◽

2014 ◽

Vol 70 (11) ◽

pp. 1025-1028

Author(s):

Hong Shen

Keyword(s):

Solid State ◽

Thermogravimetric Analysis ◽

Room Temperature ◽

Three Dimensional ◽

Fluorescence Emission ◽

Photoluminescence Properties ◽

X Ray Diffraction ◽

Strong Fluorescence ◽

X Ray ◽

Methyl Benzene

The title CdIIcoordination polymer, [Cd(C10H8O4)(C12H12N6)0.5(H2O)]n, has been obtained by the hydrothermal method and studied by single-crystal X-ray diffraction, elemental analysis, thermogravimetric analysis, IR spectroscopy and fluorescence spectroscopy. The compound forms a novel three-dimensional framework with 3,8-connected three-dimensional binodal {4.52}2{42.510.612.7.83} topology. An investigation of its photoluminescence properties shows that the compound exhibits a strong fluorescence emission in the solid state at room temperature.

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Preparation and Preliminary Characterization of Chitosan from Catharsius molossus Discards

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.548.77 ◽

2012 ◽

Vol 548 ◽

pp. 77-81

Author(s):

Jia Hua Ma ◽

Cheng Jia Tan ◽

Xia Deng ◽

Chao Xin

Keyword(s):

Fourier Transform ◽

Infrared Spectroscopy ◽

Oxalic Acid ◽

Room Temperature ◽

Orthogonal Design ◽

X Ray Diffraction ◽

X Ray ◽

Preparation Techniques ◽

Better Than

Preparation techniques of chitosan from Catharsius molossus L. processing discards were studied by orthogonal design. Preparation techniques were as follows:demineralizing: soaked for 30 min at 80 °C with 1.3 mol•L-1 HCl, then kept for 12 h under room temperature. Deproteinization and delipidation: treated for 6 h at 90 °C with 4 mol•L-1 NaOH. Decolorizing: soaked at room temperature with 3% KMnO4, then treated with 2% oxalic acid at 70 °C. Deacetylation: treated for 6 h at 110 °Cwith 14 mol•L-1 NaOH. Properties of chitosan were characterized by Fourier transform infrared spectroscopy(FTIR), X-ray diffraction (XRD), etc. It proved the technique was stable and feasible. The result also preliminarily showed that chitosan from Catharsius molossus L. was better than shrimp’s. It will be widely applicated in biomedical and other industrial areas with such exiciting properties.

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Erratum to “Crystal structures of frozen room temperature ionic liquids, 1-ethyl-3-methylimidazolium tetrafluoroborate (EMImBF4), hexafluoroniobate (EMImNbF6) and hexafluorotantalate (EMImTaF6), determined by low-temperature X-ray diffraction” [Solid State Sci. 8 (2006) 1250–1257]

Solid State Sciences ◽

10.1016/j.solidstatesciences.2007.05.009 ◽

2007 ◽

Vol 9 (8) ◽

pp. 761

Author(s):

Kazuhiko Matsumoto ◽

Rika Hagiwara ◽

Zoran Mazej ◽

Primož Benkič ◽

Boris Žemva

Keyword(s):

Ionic Liquids ◽

Solid State ◽

Low Temperature ◽

Crystal Structures ◽

Room Temperature ◽

Room Temperature Ionic Liquids ◽

X Ray Diffraction ◽

X Ray

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Thermoelectric properties of LaFeO3 system with doped Ti, Co, Cu

HUE UNIVERSITY JOURNAL OF SCIENCE NATURAL SCIENCE ◽

10.26459/hueuni-jns.v126i1b.4155 ◽

2017 ◽

Vol 126 (1B) ◽

pp. 147

Author(s):

Nguyen Thi Thuy

Keyword(s):

Electron Microscope ◽

Solid State ◽

Room Temperature ◽

Unit Cell Volume ◽

Single Phase ◽

Solid State Reaction Method ◽

X Ray Diffraction ◽

Reaction Method ◽

X Ray ◽

Scanning Electron

Abstract: LaFeO3 system with doped Ti, Co, Cu was manufactured by solid state reaction method, it was sintered at 12500C and 12900C in 10 hours with a heating rate of 30C/min. Using X-ray diffraction and Scanning Electron Microscope (SEM) to examine the structure, it reveals that samples are single-phase and orthogonal-perovskite structure describing by the Pnma space group, the unit cell volume of the samples increases when Ti, Co, Cu are doped to replace ion Fe+3. The size of particle increase while raising the temperature of sintering. Measuring the resistance which depends on temperature between the room temperature and 1000K, it can be seen that when doping Co, Cu with the nominal component La(Fe0,2Co0,2Ti0,6)O3 and La(Fe0,4Cu0,1Ti0,5)O3 , the conductivity of samples increases respectively. Especially, the conductivity of Cu doped sample is higher than two other samples, and reach the highest conductivity at about 9000C, Seebeck coefficient S of La(Fe0.6Ti0.4)O3 can be change from positive to negative at the temperature of around 7000C.

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Syntheses and crystal structures of trigonal rare-earth dioxymonocyanamides, Ln2O2CN2 (Ln=Dy, Ho, Er, Tm, Yb)

Powder Diffraction ◽

10.1154/1.2424475 ◽

2007 ◽

Vol 22 (1) ◽

pp. 59-63 ◽

Cited By ~ 8

Author(s):

Min Li ◽

Wenxia Yuan ◽

Jingfang Wang ◽

Cong Gu ◽

Huaizhou Zhao

Keyword(s):

Rare Earth ◽

Infrared Spectroscopy ◽

Solid State ◽

Rietveld Method ◽

Reaction Pathways ◽

X Ray Diffraction ◽

X Ray ◽

Cell Parameters ◽

Trigonal System ◽

Xrd Patterns

Trigonal rare-earth dioxymonocyanamides Ln2O2CN2 (Ln=Dy, Ho, Er, Tm, Yb) were synthesized by the modified solid-state metathesis (SSM) method, in which Ln2O3 and melamine C3N6H6 were mixed and heated at 850 °C in vacuumed silica ampoules. Possible chemical reaction pathways are proposed. X-ray diffraction (XRD) patterns of Ln2O2CN2 were refined using the Rietveld method. Compounds Ln2O2CN2 crystallize in the trigonal system with space group P3m1, Z=1, and cell parameters of a and c varying from 3.7267(1) to 3.6407(1) Å and from 8.1848(3) to 8.1152(3) Å, respectively, as Ln atoms change from Dy to Yb. These compounds have stacking structures of Ln2O22+ and CN22− layers, similar to those of previously reported compounds Ln2O2CN2 (Ln=Ce, Pr, Nd, Sm, Eu, Gd). The presence of CN22− ions has been confirmed by infrared spectroscopy, with two characteristic peaks in the vicinity of 651 and 2075 cm−1.

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A twofold interpenetrating three-dimensional CdIIcoordination framework: poly[[μ2-1,3-bis(2-methyl-1H-imidazol-1-yl)benzene](μ3-5-nitrobenzene-1,3-dicarboxylato)cadmium(II)]

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229614024206 ◽

2014 ◽

Vol 70 (12) ◽

pp. 1138-1142 ◽

Cited By ~ 5

Author(s):

Le Li ◽

Jian-Qing Tao

Keyword(s):

Thermal Analysis ◽

Solid State ◽

Ir Spectroscopy ◽

Room Temperature ◽

Three Dimensional ◽

Pentagonal Bipyramid ◽

Asymmetric Unit ◽

X Ray Diffraction ◽

X Ray ◽

Coordination Framework

A twofold interpenetrating three-dimensional CdIIcoordination framework, [Cd(C8H3NO6)(C14H14N4)]n, has been prepared and characterized by IR spectroscopy, elemental analysis, thermal analysis and single-crystal X-ray diffraction. The asymmetric unit consists of a divalent CdIIatom, one 1,3-bis(2-methyl-1H-imidazol-1-yl)benzene (1,3-BMIB) ligand and one fully deprotonated 5-nitrobenzene-1,3-dicarboxylate (NO2-BDC2−) ligand. The coordination sphere of the CdIIatom consists of five O-donor atoms from three different NO2-BDC2−ligands and two imidazole N-donor atoms from two different 1,3-BMIB ligands, forming a distorted {CdN2O5} pentagonal bipyramid. The NO2-BDC ligand links three CdIIatomsviaa μ1-η1:η1chelating mode and a μ2-η2:η1bridging mode. The title compound is a twofold interpenetrating 3,5-connected network with the {42.65.83}{42.6} topology. In addition, the compound exhibits fluorescence emissions in the solid state at room temperature.

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