Stepwise dehydration of Cd-exchanged levyne: thermal stability and structural modifications

AbstractZeolites show remarkable properties that can be tuned through cation exchange of their original extraframework content. In this respect, the response of the modified zeolite to the heating stimuli, in terms of structural modifications and thermal stability, can drastically change and is, therefore, an important factor to consider. In this study, the dehydration mechanism of a natural levyne previously exchanged with Cd2+ has been monitored in situ by single crystal X-ray diffraction. The initial dehydration trend between 50 and 175 °C is similar to that observed for the pristine material, levyne-Ca. The water loss is accompanied by extraframework cation migration within the zeolitic cavities and the unit-cell volume slightly contracts from 3503.8(1) to 3467.8(6) Å3. From 200 to 250 °C, a pronounced drop of the unit-cell volume (− 7%) is observed. The dehydrated structure at 250 °C corresponds to levyne B topology of natural levyne, characterized by the statistical rupture of the T–O–T bonds of the double six-ring membered cage. However, in contrast to levyne-Ca, the fraction of broken connections reached 50% instead of 37%, and no additional structural modifications were detected up to 350 °C. At 400 °C, diffraction data pointed to the onset of the structural collapse. At this temperature, the measured unit-cell volume was 8% smaller compared to that of the RT structure. The corresponding contracted structure did not rehydrate after exposure to humid conditions for 21 days.

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Study of Structural, Magnetic, and Mossbauer Properties of Dy2Fe16Ga1−xNbx (0.0 ≤ x ≤ 1.0) Prepared via Arc Melting Process

Magnetochemistry ◽

10.3390/magnetochemistry7030042 ◽

2021 ◽

Vol 7 (3) ◽

pp. 42

Author(s):

Jiba N. Dahal ◽

Kalangala Sikkanther Syed Ali ◽

Sanjay R. Mishra

Keyword(s):

Isomer Shift ◽

Cell Volume ◽

Intermetallic Compounds ◽

Unit Cell Volume ◽

Rietveld Analysis ◽

Unit Cell ◽

X Ray Diffraction ◽

X Ray ◽

Arc Melting ◽

Nb Content

Intermetallic compounds of Dy2Fe16Ga1−xNbx (x = 0.0 to 1.00) were synthesized by arc melting. Samples were investigated for structural, magnetic, and hyperfine properties using X-ray diffraction, vibration sample magnetometer, and Mossbauer spectrometer, respectively. The Rietveld analysis of room temperature X-ray diffraction data shows that all the samples were crystallized in Th2Fe17 structure. The unit cell volume of alloys increased linearly with an increase in Nb content. The maximum Curie temperature Tc ~523 K for x = 0.6 sample is higher than Tc = 153 K of Dy2Fe17. The saturation magnetization decreased linearly with increasing Nb content from 61.57 emu/g for x = 0.0 to 42.46 emu/g for x = 1.0. The Mössbauer spectra and Rietveld analysis showed a small amount of DyFe3 and NbFe2 secondary phases at x = 1.0. The hyperfine field of Dy2Fe16Ga1−xNbx decreased while the isomer shift values increased with the Nb content. The observed increase in isomer shift may have resulted from the decrease in s electron density due to the unit cell volume expansion. The substantial increase in Tc of thus prepared intermetallic compounds is expected to have implications in magnets used for high-temperature applications.

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Diffusion of Carbon into RE2Fe17(RE=RARE Earth) Lattice: A High Temperature Approach

MRS Proceedings ◽

10.1557/proc-527-87 ◽

1998 ◽

Vol 527 ◽

Author(s):

M. Venkatesan ◽

U.V. Varadaraju ◽

K.V.S. Rama Rao

Keyword(s):

Curie Temperature ◽

Cell Volume ◽

Unit Cell Volume ◽

Uniaxial Anisotropy ◽

Unit Cell ◽

X Ray Diffraction ◽

Volume Increase ◽

Melting Technique ◽

Interstitial Carbides ◽

Ga Substitution

ABSTRACTThe interstitial carbides HoErFe15Ga2Cy (y=0,0.5,1.0,1.5,2.0) were synthesized by are melting technique and characterized by X-ray diffraction and magnetization measurements. The hexagonal Th2Ni17 type structure persisted in all compounds. Both the Curie temperature TC and unit cell volume v are found to increase monotonically with increasing carbon concentration. The unit cell volume increase of Ga substituted carbide HoErFe15Ga2C2.0 is around 6.1% compared to HoErFe17. The Curie temperature increase is mainly due to the strengthening of exchange interaction. The Ga substitution is found to not only help the formation of single phase but also enhance the uniaxial anisotropy.

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Mn-rich graftonite, ferrisicklerite, staněkite and Mn-rich vivianite in a granitic pegmatite at Soè Valley, central Alps, Italy

Mineralogical Magazine ◽

10.1180/minmag.2007.071.5.579 ◽

2007 ◽

Vol 71 (5) ◽

pp. 579-585 ◽

Cited By ~ 7

Author(s):

A. Guastoni ◽

F. Nestola ◽

G. Mazzoleni ◽

P. Vignola

Keyword(s):

Single Crystal ◽

Cell Volume ◽

Unit Cell Volume ◽

Unit Cell ◽

Hydrothermal Fluids ◽

Granitic Pegmatite ◽

Single Crystal Xrd ◽

Central Alps ◽

X Ray Diffraction ◽

X Ray

AbstractMn-rich graftonite, (Ca,Mn2+)(Fe2+,Mn2+)2(PO4)2, ferrisicklerite, Li1–x(Fe3+,Mn2+)PO4, manganoan apatite, (Ca,Mn2+,Fe2+Mg)(PO4)3Cl, staně kite, Fe3+Mn2+O(PO4) and Mn-rich vivianite, (Fe2+)3(PO4)2·8H2O, occurring in a granitic pegmatite at Soè Valley (central Alps, Italy) were characterized by powder and single-crystal X-ray diffraction (XRD) and electron microprobe analyses. Geochemically, the Mn-rich graftonite phases are poorly evolved Fe/Mn-phosphates of rare-earth elements-lithium (REE-Li) granitic pegmatites. The assemblage Mn-rich graftonite + ferrisicklerite + staněkite has rarely beendocumen ted in pegmatites. Inthe Soè Valley pegmatite, ferrisicklerite forms exsolution lamellae with Mn-rich graftonite associated with manganoan apatite and staněkite. Graftonite is associated with Mn-rich vivianite. Powder and single-crystal XRD data indicate that the unit-cell volume of graftonite increases as a function of Mn2+content. Staněkite shows a distinctly smaller unit-cell volume with respect to previously reported staněkites, probably due to reduced Mn2+. Vivianite with significant Mn2+has a unit-cell volume similar to nearly Mn-free vivianite. The formation of Mn-rich graftonite and manganoan apatite is related to destabilization of Mn-rich almandine and biotite during pegmatite formation. Ferrisicklerite forms exsolution lamellae along the 010 cleavage planes of Mn-rich graftonite, whereas staněkite forms by alterationof ferrisicklerite and Mn-rich vivianite due to circulation of late-stage hydrothermal fluids.

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Structural Analysis of Platinum Nanoparticles on Carbon Nanotube Surface as Electrocatalyst System

International Journal of Chemistry ◽

10.5539/ijc.v9n2p60 ◽

2017 ◽

Vol 9 (2) ◽

pp. 60 ◽

Cited By ~ 2

Author(s):

Sudirman Sudirman ◽

Indriyati Indriyati ◽

Wisnu Ari Adi ◽

Rike Yudianti ◽

Emil Budianto

Keyword(s):

Cell Volume ◽

Unit Cell Volume ◽

Average Particle Size ◽

Unit Cell ◽

Lattice Parameters ◽

Atomic Density ◽

Average Particle ◽

X Ray Diffraction ◽

Great Opportunity ◽

X Ray

Synthesis of Pt/CNT composite by using sol gel method has been performed which the composition of CNT on the composite are vary, (x = 20, 40, 60 and 80 wt%). Performance of composite was characterized by Transmission Electron Microscope (TEM) and X-Ray Diffraction (XRD), respectively. In the refinement results of X-ray diffraction pattern, the composite consists of two phases, namely, carbon and platinum phases. Carbon phase has a structure hexagonal (P 63 m c) with lattice parameters a = b = 2.451(2) Å and c = 6.89(1) Å, α = β = 90° and γ = 120°, the unit cell volume of V = 35.8(1) A3, and the atomic density of ρ = 2.224 g.cm-3. While platinum phase has the structure of cubic (F m -3 m) with lattice parameters a = b = c = 3.921(2) Å, α = β = γ = 90°, the unit cell volume of V = 60.3(1) A3, and the atomic density of ρ = 21.487 g.cm-3.According to the image of TEM, the average particle size for Pt nano particle is estimated to range from 4.1-4.3 nm. While the cavity diameter average of CNT is estimated to range from 5.9-7.5 nm. Based on the calculation, the crystallite size of the Pt particle was around 4.31 nm. The optimum value of dispersed Pt into CNT occurred at 60 wt% CNT with the best composition of Pt in the unit cell of cystal structure. We concluded that this study successfully dispersed Pt nanoparticles onto CNT formed Pt/CNT composite. This was a great opportunity that the composite can be applied as electrocatalyst system on fuel cell application.

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X-ray powder diffraction data for 2-[((3R)-5-oxo-4-phenyltetrahy drofuran-3-yl)methyl]isoindoline-1,3-dione, C19H15NO4

Powder Diffraction ◽

10.1017/s0885715616000105 ◽

2016 ◽

Vol 31 (2) ◽

pp. 155-158

Author(s):

Shoujun Zheng ◽

Kailin Xu ◽

Qing Wang ◽

XiaoLin Tang ◽

Yanmei Huang ◽

...

Keyword(s):

Cell Volume ◽

Powder Diffraction ◽

Unit Cell Volume ◽

Unit Cell ◽

X Ray Diffraction ◽

Orthorhombic Space Group ◽

Element Analysis ◽

Space Group ◽

X Ray ◽

Cell Parameters

2-[((3R)-5-oxo-4-phenyltetrahydrofuran-3-yl)methyl]isoindoline-1,3-dione, C19H15NO4, was synthesized for the first time. Its structure was characterized by element analysis, ultraviolet spectrometry, nuclear magnetic resonance, and single X-ray diffraction (SXRD). X-ray powder diffraction (XRPD) data of title compound were collected and calculated. The result of SXRD shows that its crystal system is orthorhombic, space group is Pbca, and unit-cell parameters are a = 8.861 57(7), b = 14.6666(10), c = 24.4247(19) Å, α =β =γ =90°, unit-cell volume V = 3174.4 Å3, and Z = 8. All XRPD measured lines were indexed and consistent with the Pbca space group [a = 14.639(7), b = 24.378(3), c = 8.918(1) Å, α = β = γ = 90°, unit-cell volume V = 3182.7(9) Å3, Z = 8]. No detectable impurities were observed.

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X-ray diffraction data of 4-phenyl-6-(trifluoromethyl)-3,4-dihydroquinolin-2(1H)-one and its synthetic precursor N-[4-(trifluoromethyl)phenyl]cinnamamide

Powder Diffraction ◽

10.1017/s0885715616000282 ◽

2016 ◽

Vol 31 (3) ◽

pp. 233-239

Author(s):

Jose H. Quintana Mendoza ◽

J. A. Henao ◽

Carlos E. Rondón Flórez ◽

Carlos E. Puerto Galvis ◽

Vladimir V. Kouznetsov

Keyword(s):

Cell Volume ◽

Title Compound ◽

Unit Cell Volume ◽

Unit Cell ◽

Chemical Formula ◽

X Ray Diffraction ◽

Unit Cell Parameters ◽

Monoclinic System ◽

X Ray ◽

Cell Parameters

The title compound, the 4-phenyl-6-(trifluoromethyl)-3,4-dihydroquinolin-2(1H)-one (4) with chemical formula: (C16H12F3NO), was synthesized from N-[4-(trifluoromethyl)phenyl]cinnamamide (3), chemical formula: (C16H12F3NO), through an intramolecular cyclization mediated by triflic acid. Preliminary molecular characterization of both compounds was performed by Fourier transform infrared spectroscopy, gas chromatography mass spectrometry, and nuclear magnetic resonance spectroscopy (1H, 13C); crystallographic characterization was completed by X-ray diffraction of polycrystalline samples. The title compound 4 crystallized in a monoclinic system and unit-cell parameters are reported [a = 16.002 (3), b = 5.170 (1), c = 17.733 (3) Å, β = 111.11 (2)°, unit-cell volume V = 1368.5 (3) Å3, Z = 4] P21/c (No. 14) space group; the title compound 3 crystallized in a monoclinic system and unit-cell parameters are reported [a = 12.902 (2), b = 5.144 (1), c = 20.513 (5) Å, β = 91.67 (2)°, unit-cell volume V = 1360.7 (4) Å3, Z = 4] P21/c (No. 14) space group.

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Crystal Chemistry and Structural Variations for Zircon Samples from Various Localities

Minerals ◽

10.3390/min10110947 ◽

2020 ◽

Vol 10 (11) ◽

pp. 947 ◽

Cited By ~ 2

Author(s):

M. Zaman ◽

Sytle Antao

Keyword(s):

Cell Volume ◽

Unit Cell Volume ◽

Structural Parameters ◽

Unit Cell ◽

Radiation Doses ◽

X Ray Diffraction ◽

Unit Cell Parameters ◽

X Ray ◽

Cell Parameters ◽

Zircon Sample

This study investigates the variations of structural parameters and chemistry of a partially metamict and seven detrital zircon samples from different localities using single-crystal X-ray diffraction, synchrotron high-resolution powder X-ray diffraction, and electron-probe micro-analysis techniques. The unit-cell parameters for the eight zircon samples vary linearly with increasing unit-cell volume, V. A zircon sample from the Canadian Arctic Islands has the smallest unit-cell parameters, bond distances, ideal stoichiometric composition, unaffected by α-radiation damage, and is chemically pure. A zircon sample from Jemaa, Nigeria has the largest unit-cell parameters because of the effect of α-radiation doses received over a long time (2384 Ma). All the samples show good correlations between Zr and Si apfu (atom per formula unit) versus unit-cell volume, V. The α-radiation doses in the samples are lower than ~3.5 × 1015 α-decay events/mg. Substitutions of other cations at the Zr and Si sites control the variations of the structural parameters. Relatively large unit-cell parameters and bond distances occur because the Zr site accommodates other cations that have larger ionic radii than the Zr atom. Geological age increases the radiation doses in zircon and it is related to V.

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Powder X-ray diffraction of 1-(4-aminophenyl)-5,6-dihydro-3-(4-morpholinyl)-2(1H)-pyridinone, C15H19N3O2

Powder Diffraction ◽

10.1017/s088571561500072x ◽

2015 ◽

Vol 30 (4) ◽

pp. 367-367 ◽

Cited By ~ 2

Author(s):

Qing Wang ◽

Ya Ping Li ◽

Shan Shan Li ◽

Bin Tang ◽

Hui Li

Keyword(s):

Cell Volume ◽

Powder Diffraction ◽

Diffraction Data ◽

Unit Cell Volume ◽

Unit Cell ◽

Powder Diffraction Data ◽

X Ray Diffraction ◽

Space Group ◽

X Ray

X-ray powder diffraction data for 1-(4-aminophenyl)-5,6-dihydro-3-(4-morpholinyl)-2(1H)-pyridinone, C15H19N3O2, are reported [a = 14.877(4) Å, b = 5.893(6) Å, c = 18.984(3) Å, α = 90°, β = 122.298(3)°, γ = 90°, unit-cell volume V = 1406.86 Å3, Z = 4, and space group P21/c]. All measured lines were indexed and are consistent with the P21/c space group. No detectable impurities were observed.

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Synthesis, Characterization and Biological Studies of Ether–Based Ferrocenyl Amides and their Organic Analogues

Crystals ◽

10.3390/cryst10060480 ◽

2020 ◽

Vol 10 (6) ◽

pp. 480

Author(s):

Sana Waseem Abbasi ◽

Naveed Zafar Ali ◽

Martin Etter ◽

Muhammad Shabbir ◽

Zareen Akhter ◽

...

Keyword(s):

Single Crystal ◽

Cell Volume ◽

Crystal Structures ◽

Unit Cell Volume ◽

Unit Cell ◽

Spectral Studies ◽

Scavenging Activity ◽

X Ray Diffraction ◽

Space Group ◽

X Ray

Ferrocenyl amides (FB1-FB13) and their organic analogues (BZ1-BZ13) were prepared by a low-temperature condensation method. Ferrocenyl amides were synthesised using 4-ferrocenylbenzoyl chloride and ether-based amines and diamines. Benzoyl chloride was used to synthesise organic analogues by reacting with various amines. The synthesised compounds were characterised by elemental, spectroscopic (FT-IR and NMR) and single crystal X-ray diffraction methods. Crystal structures of the representative organic analogues (BZ2 and BZ6) were solved by single crystal X-ray diffraction. BZ2 crystallises in the triclinic space group P 1 ¯ with a unit cell volume of V = 1056.6(3) Å3 and with two formula units per unit cell. Whereas BZ6 assembles in the orthorhombic space group Pbca with four formula units per unit cell and a unit cell volume of V = 1354.7(2) Å3. Spectral studies confirmed the presence of amide linkages in the synthesised compound with a strong N—H·····O=C hydrogen bonding network established between amide groups of neighbouring molecular scaffolds further stabilising the molecular stacking in accordance with the archetypal crystal structures. The bioactive nature of each compound was assessed by DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging activity, hydrogen peroxide scavenging activity and total antioxidant activity. Antidiabetic, anticholinesterase enzyme inhibition tests, as well as antibacterial activities, were performed showing significant biological activity for ferrocenyl amides as compared to their organic analogues.

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Single Crystal X-Ray Structural Investigation of Alluaudite Related Monophosphate Na2FeMn2(PO4)3

Eurasian Chemico-Technological Journal ◽

10.18321/ectj47 ◽

2010 ◽

Vol 12 (3,4) ◽

pp. 213

Author(s):

Nezha Dridi ◽

El Hassan Arbib ◽

El Hassan Karni ◽

Francesco Capitelli ◽

Brahim Elouadi

Keyword(s):

Single Crystal ◽

Cell Volume ◽

Unit Cell Volume ◽

Structural Investigation ◽

Three Dimensional ◽

Structural Type ◽

Unit Cell ◽

X Ray Diffraction ◽

X Ray ◽

Dimensional Network

The compound Na2FeMn2(PO4)3 has been successfully isolated with the alluaudite structural type. Accurate single crystal X-Ray diffraction has allowed solving the structure with reliability factors of R1 and Rw equal to 0.0322 and 0.0790 respectively. It was found that the symmetry is monoclinic with a space group of C2/c and lattice parameters: a = 12.180(2) Å, b = 12.660(2) Å, c = 6.500(2) Å, b = 114.528(3)(°), unit cell volume = 911.8(3) Å3, Z = 8 and dcal.=3.618 g.cm-3. Three-dimensional network is formed by the [MnO6] octahedra linked in pairs to form Mn-based octahedral dimers: ([Mn2O10]). Each dimer shares six vertices with six tetrahedra [P(2)O4] to form sheets within the plane (100). The latter are connected by tetrahedra [P(1)O4] delimiting cages and tunnels which house either Fe3+ or Na+ cations. Each [FeO6] octahedron is linked to two [Mn2O10] dimers belonging to two adjacent sheets to form mixed Fe-Mn chains of the type: - Fe3+ - Mn2+ - Mn2+ - Fe3+ - Mn2+ - Mn2+ - Fe3+ - ..., running along the direction [101].

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