Anisotropic compressibility of the coordination polymer emim[Mn(btc)]

The effect of pressure on the crystal structure of a coordination polymer, emim[MnII(btc)] (emim = 1-ethyl,3-methyl imidazolium cation, btc = 1,3,5-benzene-tricarboxylate), was investigated with single-crystal X-ray diffraction. At 4.3 GPa the unit-cell volume had decreased by 14% compared with ambient conditions. The unit-cell contraction is highly anisotropic, with thea- andb-axes decreasing by 5.5 and 9.5%, respectively, and thec-axis compressing a mere 0.25% up to 1.7 GPa followed by a 0.2% expansion between 1.7 and 4.3 GPa. The 0.2% increase in length of thec-axis in this interval happens above the quasi-hydrostatic limit of the pressure-transmitting medium and therefore it might be a consequence of strain gradients. Under ambient conditions, two MnO6units are connected by two carboxylate ligands to form dimeric units. On increasing pressure, a non-bonded O atom from a bridging carboxylate group approaches the Mn atom, with the Mn—O distance decreasing from 2.866 (1) Å at 0.3 GPa to 2.482 (6) Å at 4.3 GPa, increasing the coordination environment of the Mn ion from six- to seven-coordinated.

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Structure and X-ray reference diffraction patterns of (Ba6−xSrx)R2Co4O15 (x = 1, 2) (R = lanthanides)

Powder Diffraction ◽

10.1017/s0885715613000171 ◽

2013 ◽

Vol 28 (3) ◽

pp. 212-221 ◽

Cited By ~ 2

Author(s):

W. Wong-Ng ◽

G. Liu ◽

Y.G. Yan ◽

J.A. Kaduk

Keyword(s):

General Structure ◽

Unit Cell ◽

X Ray Diffraction ◽

Unit Cell Parameters ◽

Powder Diffraction File ◽

Coordination Environment ◽

X Ray ◽

Cell Parameters ◽

Diffraction Patterns ◽

Ray Patterns

The structure and X-ray patterns of two series of barium lanthanide cobaltates, namely, Ba4Sr2R2Co4O15 (R = La, Nd, Sm, Eu, Gd, and Dy), and Ba5SrR2Co4O15 (R = La, Nd, Sm, Eu, and Gd) have been determined. These compounds crystallize in the space group P63mc; the unit-cell parameters of Ba4Sr2R2Co4O15 (R from La to Dy) decrease from a = 11.6128(2) Å to 11. 5266(9) Å, c = 6.869 03(11) to 6. 7630(5) Å, and V = 802.23(3) Å3 to 778.17(15) Å3, respectively. In the Ba5SrR2Co4O15 series (R = La to Gd), the unit-cell parameters decrease from a = 11.735 44(14) Å to 11.619 79(12) Å, c = 6.942 89 (14) Å to 6.836 52(8) Å, and V = 828.08(3) Å3 to 799.40(2) Å3. In the general structure of (Ba6−xSrx)R2Co4O15, there are four Co ions per formula unit occupying one CoO6 octahedral and three CoO4 tetrahedral units. Through corner-sharing of these polyhedra, a larger Co4O15 unit is formed. Sr2+ ions adopt both octahedral and 8-fold coordination environment. R3+ ions adopt 8-fold coordination (mixed site with Sr), while the larger Ba2+ ions assume both 10- and 11-fold coordination environments. The samples were found to be insulators. X-ray diffraction patterns of these samples have been determined and submitted to the Powder Diffraction File (PDF).

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Manganese(II) chloride complexes with pyridineN-oxide (PNO) derivatives and their solid-state structures

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s2056989017012038 ◽

2017 ◽

Vol 73 (10) ◽

pp. 1434-1438 ◽

Cited By ~ 2

Author(s):

Linda Kang ◽

Genevieve Lynch ◽

Will Lynch ◽

Clifford Padgett

Keyword(s):

Hydrogen Bonding ◽

Solid State ◽

Coordination Polymer ◽

Single Crystal ◽

Metal Cation ◽

X Ray Diffraction ◽

Chloride Complexes ◽

Coordination Environment ◽

X Ray ◽

Solid State Structures

Three manganese(II)N-oxide complexes have been synthesized from the reaction of manganese(II) chloride with either pyridineN-oxide (PNO), 2-methylpyridineN-oxide (2MePNO) or 3-methylpyridineN-oxide (3MePNO). The compounds were synthesized from methanolic solutions of MnCl2·4H2O and the respectiveN-oxide, and subsequently characterized structurally by single-crystal X-ray diffraction. The compounds arecatena-poly[[aquachloridomanganese(II)]-di-μ-chlorido-[aquachloridomanganese(II)]-bis(μ-pyridineN-oxide)], [MnCl2(C5H5NO)(H2O)]nor [MnCl2(PNO)(H2O)]n(I),catena-poly[[aquachloridomanganese(II)]-di-μ-chlorido-[aquachloridomanganese(II)]-bis(μ-2-methylpyridineN-oxide)], [MnCl2(C6H7NO)(H2O)]nor [MnCl2(2MePNO)(H2O)]n(II), and bis(μ-3-methylpyridineN-oxide)bis[diaquadichloridomanganese(II)], [Mn2Cl4(C6H7NO)2(H2O)4] or [MnCl2(3MePNO)(H2O)2]2(III). The MnIIatoms are found in pseudo-octahedral environments for each of the three complexes. CompoundIforms a coordination polymer with alternating pairs of bridgingN-oxide and chloride ligands. The coordination environment is defined by two PNO bridging O atoms, two chloride bridging atoms, a terminal chloride, and a terminal water. CompoundIIalso forms a coordination polymer with a similar metal cation; however, the coordination polymer is bridged between MnIIatoms by both a single chloride and 2MePNO. The distorted octahedrally coordinated metal cation is defined by two bridging 2MePNOtransto each other, two chlorides, alsotransto one another in the equatorial (polymeric) plane, and a terminal chloride and terminal water. Finally, complexIIIforms a dimer with two bridging 3MePNOs, two terminal chlorides and two terminal waters forming the six-coordinate metal environment. All three compounds exhibit hydrogen bonding between the coordinating water(s) and terminal chlorides.

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Fabrication and study the effect of the laser on the properties of the compound Tl2-xHgxBa2-ySryCa2Cu3O10+δ superconductor

Ibn AL- Haitham Journal For Pure and Applied Science ◽

10.30526/2017.ihsciconf.1789 ◽

2018 ◽

pp. 168

Author(s):

A. Kareem Dahash Ali ◽

Nihad Ali Shafeek

Keyword(s):

Transition Temperature ◽

Solid State ◽

Hydrostatic Pressure ◽

Electrical Properties ◽

Co2 Laser ◽

Temperature Shift ◽

Unit Cell ◽

X Ray Diffraction ◽

X Ray ◽

Structural And Electrical Properties

This study included the fabrication of compound (Tl2-xHgxBa2-ySryCa2Cu3O10+δ) in a manner solid state and under hydrostatic pressure ( 8 ton/cm2) and temperature annealing(850°C), and determine the effect of the laser on the structural and electrical properties elements in the compound, and various concentrations of x where (x= 0.1,0.2,0.3 ). Observed by testing the XRD The best ratio of compensation for x is 0.2 as the value of a = b = 5.3899 (A °), c = 36.21 (A °) show that the installation of four-wheel-based type and that the best temperature shift is TC= 142 K .When you shine a CO2 laser on the models in order to recognize the effect of the laser on these models showed the study of X-ray diffraction of these samples when preparing models with different concentrations of the values of x, the best ratio of compensation is 0.2 which showed an increase in the values of the dimensions of the unit cell a=b = 5.3929 (A °), c = 36.238 (A°). And the best transition temperature after shedding laser is TC=144 K.

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A 2-D Zn(II) coordination polymer based on 4,5-imidazoledicarboxylate and bis(benzimidazole) ligands: synthesis, crystal structure and fluorescence properties

Zeitschrift für Naturforschung B ◽

10.1515/znb-2021-0003 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Xinzhao Xia ◽

Lixian Xia ◽

Geng Zhang ◽

Yuxuan Jiang ◽

Fugang Sun ◽

...

Keyword(s):

Crystal Structure ◽

Coordination Polymer ◽

Zigzag Chain ◽

Supramolecular Framework ◽

X Ray Diffraction ◽

Hydrothermal Conditions ◽

Hydrogen Bond Interaction ◽

X Ray ◽

New Type ◽

Solid State Fluorescence

Abstract In this work, a new type of zinc(II) coordination polymer {[Zn(HIDC)(BBM)0.5]·H2O} n (Zn-CP) was synthesized using 4,5-imidazoledicarboxylic acid (H3IDC) and 2,2-(1,4-butanediyl)bis-1,3-benzimidazole (BBM) under hydrothermal conditions. Its structure has been characterized by infrared spectroscopy, elemental analysis and single crystal X-ray diffraction analysis. The Zn(II) ion is linked by the HIDC2− ligand to form a zigzag chain by chelating and bridging, and then linked by BBM to form a layered network structure. Adjacent layers are further connected by hydrogen bond interaction to form a 3-D supramolecular framework. The solid-state fluorescence performance of Zn-CP shows that compared with free H3IDC ligand, its fluorescence intensity is significantly enhanced.

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Pyrene Carboxylate Ligand Based Coordination Polymers for Microwave-Assisted Solvent-Free Cyanosilylation of Aldehydes

Molecules ◽

10.3390/molecules26041101 ◽

2021 ◽

Vol 26 (4) ◽

pp. 1101

Author(s):

Anirban Karmakar ◽

Anup Paul ◽

Elia Pantanetti Sabatini ◽

M. Fátima C. Guedes da Silva ◽

Armando J. L. Pombeiro

Keyword(s):

Coordination Polymer ◽

Single Crystal ◽

Coordination Polymers ◽

Metal Ion ◽

Solvent Free ◽

Lewis Acidity ◽

Carboxylate Ligand ◽

X Ray Diffraction ◽

X Ray ◽

Microwave Assisted

The new coordination polymers (CPs) [Zn(μ-1κO1:1κO2-L)(H2O)2]n·n(H2O) (1) and [Cd(μ4-1κO1O2:2κN:3,4κO3-L)(H2O)]n·n(H2O) (2) are reported, being prepared by the solvothermal reactions of 5-{(pyren-4-ylmethyl)amino}isophthalic acid (H2L) with Zn(NO3)2.6H2O or Cd(NO3)2.4H2O, respectively. They were synthesized in a basic ethanolic medium or a DMF:H2O mixture, respectively. These compounds were characterized by single-crystal X-ray diffraction, FTIR spectroscopy, thermogravimetric and elemental analysis. The single-crystal X-ray diffraction analysis revealed that compound 1 is a one dimensional linear coordination polymer, whereas 2 presents a two dimensional network. In both compounds, the coordinating ligand (L2−) is twisted due to the rotation of the pyrene ring around the CH2-NH bond. In compound 1, the Zn(II) metal ion has a tetrahedral geometry, whereas, in 2, the dinuclear [Cd2(COO)2] moiety acts as a secondary building unit and the Cd(II) ion possesses a distorted octahedral geometry. Recently, several CPs have been explored for the cyanosilylation reaction under conventional conditions, but microwave-assisted cyanosilylation of aldehydes catalyzed by CPs has not yet been well studied. Thus, we have tested the solvent-free microwave-assisted cyanosilylation reactions of different aldehydes, with trimethylsilyl cyanide, using our synthesized compounds, which behave as highly active heterogeneous catalysts. The coordination polymer 1 is more effective than 2, conceivably due to the higher Lewis acidity of the Zn(II) than the Cd(II) center and to a higher accessibility of the metal centers in the former framework. We have also checked the heterogeneity and recyclability of these coordination polymers, showing that they remain active at least after four recyclings.

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X-ray Diffraction Analysis and Williamson-Hall Method in USDM Model for Estimating More Accurate Values of Stress-Strain of Unit Cell and Super Cells (2 × 2 × 2) of Hydroxyapatite, Confirmed by Ultrasonic Pulse-Echo Test

Materials ◽

10.3390/ma14112949 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2949

Author(s):

Marzieh Rabiei ◽

Arvydas Palevicius ◽

Amir Dashti ◽

Sohrab Nasiri ◽

Ahmad Monshi ◽

...

Keyword(s):

Young’S Modulus ◽

Young's Modulus ◽

Ultrasonic Pulse ◽

High Accuracy ◽

Unit Cell ◽

Deformation Model ◽

X Ray Diffraction ◽

Uniform Deformation ◽

X Ray ◽

Pulse Echo

Taking into account X-ray diffraction, one of the well-known methods for calculating the stress-strain of crystals is Williamson-Hall (W–H). The W-H method has three models, namely (1) Uniform deformation model (UDM); (2) Uniform stress deformation model (USDM); and (3) Uniform deformation energy density model (UDEDM). The USDM and UDEDM models are directly related to the modulus of elasticity (E). Young’s modulus is a key parameter in engineering design and materials development. Young’s modulus is considered in USDM and UDEDM models, but in all previous studies, researchers used the average values of Young’s modulus or they calculated Young’s modulus only for a sharp peak of an XRD pattern or they extracted Young’s modulus from the literature. Therefore, these values are not representative of all peaks derived from X-ray diffraction; as a result, these values are not estimated with high accuracy. Nevertheless, in the current study, the W-H method is used considering the all diffracted planes of the unit cell and super cells (2 × 2 × 2) of Hydroxyapatite (HA), and a new method with the high accuracy of the W-H method in the USDM model is presented to calculate stress (σ) and strain (ε). The accounting for the planar density of atoms is the novelty of this work. Furthermore, the ultrasonic pulse-echo test is performed for the validation of the novelty assumptions.

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Pressure-induced Jahn-Teller Switch in the Homoleptic Hybrid Perovskite [(CH3)2NH2]Cu(HCOO)3: Orbital Reordering by Unconventional Degrees of Freedom

Journal of Materials Chemistry C ◽

10.1039/d1tc01966j ◽

2021 ◽

Author(s):

Rebecca Scatena ◽

Michał Andrzejewski ◽

Roger D Johnson ◽

Piero Macchi

Keyword(s):

Phase Transition ◽

High Pressure ◽

Coordination Polymer ◽

Degrees Of Freedom ◽

X Ray Diffraction ◽

X Ray ◽

Hybrid Perovskite ◽

Jahn Teller

Through in-situ, high-pressure x-ray diffraction experiments we have shown that the homoleptic perovskite-like coordination polymer [(CH3)2NH2]Cu(HCOO)3 undergoes a pressure-induced orbital reordering phase transition above 5.20 GPa. This transition is distinct...

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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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Crystal Structure Refinements of Four Monazite Samples from Different Localities

Minerals ◽

10.3390/min10111028 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1028 ◽

Cited By ~ 1

Author(s):

M. Mashrur Zaman ◽

Sytle M. Antao

Keyword(s):

Crystal Structure ◽

Electron Probe ◽

Unit Cell Volume ◽

Unit Cell ◽

X Ray Diffraction ◽

Unit Cell Parameters ◽

X Ray ◽

Cell Parameters ◽

Large Unit Cell ◽

A Site

This study investigates the crystal chemistry of monazite (APO4, where A = Lanthanides = Ln, as well as Y, Th, U, Ca, and Pb) based on four samples from different localities using single-crystal X-ray diffraction and electron-probe microanalysis. The crystal structure of all four samples are well refined, as indicated by their refinement statistics. Relatively large unit-cell parameters (a = 6.7640(5), b = 6.9850(4), c = 6.4500(3) Å, β = 103.584(2)°, and V = 296.22(3) Å3) are obtained for a detrital monazite-Ce from Cox’s Bazar, Bangladesh. Sm-rich monazite from Gunnison County, Colorado, USA, has smaller unit-cell parameters (a = 6.7010(4), b = 6.9080(4), c = 6.4300(4) Å, β = 103.817(3)°, and V = 289.04(3) Å3). The a, b, and c unit-cell parameters vary linearly with the unit-cell volume, V. The change in the a parameter is large (0.2 Å) and is related to the type of cations occupying the A site. The average <A-O> distances vary linearly with V, whereas the average <P-O> distances are nearly constant because the PO4 group is a rigid tetrahedron.

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Compressibility of β-As4S4: an in situ high-pressure single-crystal X-ray study

Mineralogical Magazine ◽

10.1180/minmag.2012.076.4.12 ◽

2012 ◽

Vol 76 (4) ◽

pp. 963-973 ◽

Cited By ~ 6

Author(s):

G. O. Lepore ◽

T. Boffa Ballaran ◽

F. Nestola ◽

L. Bindi ◽

D. Pasqual ◽

...

Keyword(s):

Pressure Range ◽

Substantial Reduction ◽

Structural Data ◽

Unit Cell ◽

Van Der Waals Interactions ◽

X Ray Diffraction ◽

Unit Cell Parameters ◽

X Ray ◽

Cell Parameters ◽

Intermolecular Distances

AbstractAmbient temperature X-ray diffraction data were collected at different pressures from two crystals of β-As4S4, which were made by heating realgar under vacuum at 295ºC for 24 h. These data were used to calculate the unit-cell parameters at pressures up to 6.86 GPa. Above 2.86 GPa, it was only possible to make an approximate measurement of the unit-cell parameters. As expected for a crystal structure that contains molecular units held together by weak van der Waals interactions, β-As4S4 has an exceptionally high compressibility. The compressibility data were fitted to a third-order Birch–Murnaghan equation of state with a resulting volume V0 = 808.2(2) Å3, bulk modulus K0 = 10.9(2) GPa and K' = 8.9(3). These values are extremely close to those reported for the low-temperature polymorph of As4S4, realgar, which contains the same As4S4 cage-molecule. Structural analysis showed that the unit-cell contraction is due mainly to the reduction in intermolecular distances, which causes a substantial reduction in the unit-cell volume (∼21% at 6.86 GPa). The cage-like As4S4 molecules are only slightly affected. No phase transitions occur in the pressure range investigated.Micro-Raman spectra, collected across the entire pressure range, show that the peaks associated with As–As stretching have the greatest pressure dependence; the S–As–S bending frequency and the As–S stretching have a much weaker dependence or no variation at all as the pressure increases; this is in excellent agreement with the structural data.

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