scholarly journals Structure of magnesium selenate enneahydrate, MgSeO4·9H2O, from 5 to 250 K using neutron time-of-flight Laue diffraction

2015 ◽  
Vol 71 (3) ◽  
pp. 313-327 ◽  
Author(s):  
A. Dominic Fortes ◽  
Dario Alfè ◽  
Eduardo R. Hernández ◽  
Matthias J. Gutmann
Keyword(s):  
Density Functional ◽  
Crystal Morphology ◽  
Water Molecules ◽  
Monoclinic Space Group ◽  
Single Crystal Diffraction ◽  
Functional Theory ◽  
X Ray ◽  
Cell Parameters ◽  
Diffraction Structure ◽  
Neutron Time

The complete structure of MgSeO4·9H2O has been refined from neutron single-crystal diffraction data obtained at 5, 100, 175 and 250 K. It is monoclinic, space groupP21/c,Z= 4, with unit-cell parametersa= 7.222 (2),b= 10.484 (3),c= 17.327 (4) Å, β = 109.57 (2)°, andV= 1236.1 (6) Å3[ρcalc= 1770 (1) kg m−3] at 5 K. The structure consists of isolated [Mg(H2O)6]2+octahedra, [SeO4]2−tetrahedra and three interstitial lattice water molecules, all on sites of symmetry 1. The positions of the H atoms agree well with those inferred on the basis of geometrical considerations in the prior X-ray powder diffraction structure determination: no evidence of orientational disorder of the water molecules is apparent in the temperature range studied. Six of the nine water molecules are hydrogen bonded to one another to form a unique centrosymmetric dodecamer, (H2O)12. Raman spectra have been acquired in the range 170–4000 cm−1at 259 and 78 K;ab initiocalculations, using density functional theory, have been carried out in order to aid in the analysis of the Raman spectrum as well as providing additional insights into the geometry and thermodynamics of the hydrogen bonds. Complementary information concerning the thermal expansion, crystal morphology and the solubility are also presented.

A new BaCa(CO3)2 polymorph

2019 ◽  
Vol 75 (3) ◽  
pp. 291-300
Author(s):  
Dominik Spahr ◽  
Lkhamsuren Bayarjargal ◽  
Victor Vinograd ◽  
Rita Luchitskaia ◽  
Victor Milman ◽  
...  
Keyword(s):  
Density Functional ◽  
Rietveld Analysis ◽  
Radioactive Isotopes ◽  
Synthesis Product ◽  
Monoclinic Space Group ◽  
Unit Cell Parameters ◽  
Functional Theory ◽  
Model Calculations ◽  
X Ray ◽  
Cell Parameters

A new polymorph of the double carbonate BaCa(CO3)2, `a C2 phase', has been synthesized. Its structure has been obtained by density-functional-theory-based (DFT-based) model calculations and has been refined by Rietveld analysis of X-ray powder diffraction data. The structure of the new polymorph differs significantly from those of the established polymorphs barytocalcite, paralstonite and alstonite. The unit-cell parameters of the new monoclinic (space group C2) compound are a = 6.6775 (5), b = 5.0982 (4), c = 4.1924 (3) Å, β = 109.259 (1)°. The new compound has been further characterized using Raman spectroscopy. This work shows that earlier studies have misidentified the products of an established synthesis route and that findings based on the incorrect identification of the synthesis product concerning the suitability of barytocalcite as a matrix for the retention of radioactive isotopes will need to be reconsidered.

scholarly journals Synthesis, Crystal Structure, Thermal Analysis, and DFT Calculations of Molecular Copper(II) Chloride Complexes with Bitopic Ligand 1,1,2,2-tetrakis(pyrazol-1-yl)ethane

Crystals ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 222
Author(s):  
Lider ◽  
Sukhikh ◽  
Smolentsev ◽  
Semitut ◽  
Filatov ◽  
...  
Keyword(s):  
Dft Calculations ◽  
Coordination Compounds ◽  
Density Functional ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
Chloride Complexes ◽  
Functional Theory ◽  
X Ray ◽  
Lattice Water ◽  
Ir Bands

Two binuclear coordination compounds of Cu(II) chloride with the bitopic ligand 1,1,2,2-tetrakis(pyrazol-1-yl)ethane (Pz4) of the composition [Cu2(µ2Pz4)(DMSO)2Cl4]·4H2O and [Cu2(µ2Pz4)(DMSO)2Cl4]∙2DMSO were prepared and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, single-crystal X-ray diffraction, and powder diffraction analysis. It was shown that in contrast to silver(I) and copper(II) nitrates, copper(II) chloride forms discrete complexes instead of coordination polymers. The supramolecular structure of the complex [Cu2(µ2Pz4)(DMSO)2Cl4]·4H2O with lattice water molecules is formed by OH···Cl and OH···O hydrogen bonds. Density functional theory (DFT) calculations of vibrational frequencies of the ligand and its copper(II) complex allowed for assigning IR bands to specific vibrations.

scholarly journals Synthesis, Characterization, and Crystal Structure Determination of a New Lithium Zinc Iodate Polymorph LiZn(IO3)3

Crystals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 464 ◽  
Author(s):  
Hebboul ◽  
Galez ◽  
Benbertal ◽  
Beauquis ◽  
Mugnier ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Density Functional Theory ◽  
Density Functional ◽  
Second Harmonic ◽  
Infrared Absorption Spectrum ◽  
Density Functional Theory Calculations ◽  
Functional Theory ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters

Synthesis and characterization of anhydrous LiZn(IO3)3 powders prepared from an aqueous solution are reported. Morphological and compositional analyses were carried out by using scanning electron microscopy and energy-dispersive X-ray measurements. The synthesized powders exhibited a needle-like morphology after annealing at 400 °C. A crystal structure for the synthesized compound was proposed from powder X-ray diffraction and density-functional theory calculations. Rietveld refinements led to a monoclinic structure, which can be described with space group P21, number 4, and unit-cell parameters a = 21.874(9) Å, b = 5.171(2) Å, c = 5.433(2) Å, and  = 120.93(4)°. Density-functional theory calculations supported the same crystal structure. Infrared spectra were also collected, and the vibrations associated with the different modes were discussed. The non-centrosymmetric space group determined for this new polymorph of LiZn(IO3)3, the characteristics of its infrared absorption spectrum, and the observed second-harmonic generation suggest it is a promising infrared non-linear optical material.

scholarly journals Disodium hydrogen citrate sesquihydrate, Na2HC6H5O7(H2O)1.5

2016 ◽  
Vol 72 (7) ◽  
pp. 943-946 ◽  
Author(s):  
Alagappa Rammohan ◽  
Amy A. Sarjeant ◽  
James A. Kaduk
Keyword(s):  
Crystal Structure ◽  
Density Functional ◽  
Water Molecules ◽  
Asymmetric Unit ◽  
Single Crystal Diffraction ◽  
Coordination Polyhedra ◽  
X Ray ◽  
Carboxylic Acid Groups ◽  
Sodium Cations ◽  
Disodium Hydrogen Citrate

The crystal structure of disodium hydrogen citrate sesquihydrate, 2Na2+·C6H6O72−·1.5H2O, has been solved and refined using laboratory X-ray single-crystal diffraction data, and optimized using density functional techniques. The asymmetric unit contains two independent hydrogen citrate anions, four sodium cations and three water molecules. The coordination polyhedra of the cations (three with a coordination number of six, one with seven) share edges to form isolated 8-rings. The un-ionized terminal carboxylic acid groups form very strong hydrogen bonds to non-coordinating O atoms, with O...O distances of 2.46 Å.

Préparation, Identification et Radiocristallographie d'un Hétérocycle Cétonique à Intérêt Médicinal: l'Isopropyl-3, phényl-2, diaza-1,3, one-5 bicyclo [3,3,0] octène-1

1990 ◽  
Vol 5 (1) ◽  
pp. 48-49
Author(s):  
Par Mme C. Caranoni ◽  
M.J.P. Reboul ◽  
Melle C. Soula
Keyword(s):  
Chemical Analysis ◽  
Single Crystal ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Monoclinic Space Group ◽  
Powder Diffraction Data ◽  
Single Crystal Diffraction ◽  
X Ray ◽  
Cell Parameters ◽  
Better Than

AbstractThe heterocycle of a functionalized 2-imidazoline, C15N2OH18, was obtained by reaction when 2-bromo, 2-alkenoïc ketone was allowed to react with a monosubstituted benzamidine. The compound presents a R*R* configuration. X-ray powder diffraction data have been obtained from single multifaceted brown crystals prepared at 273 K in benzene with triethylamine as catalyst. Chemical analysis gives a purity better than 99%. This compound crystallizes in the monoclinic space group P21/c [14]. The cell parameters were determined by employing single-crystal diffraction methods (Bragg and precession patterns) and were refined from accurate powder diffractometer data recorded at T = 293 (1) K.

scholarly journals Aqueous Micro-hydration of Na+(H2O)n=1-7 Clusters: DFT Study

2019 ◽  
Vol 17 (1) ◽  
pp. 260-269 ◽  
Author(s):  
Tahoon M.A. ◽  
Gomaa E.A. ◽  
Suleiman M.H.A.
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Hydration Number ◽  
Sodium Ion ◽  
Water Molecules ◽  
Functional Theory ◽  
Water Binding ◽  
X Ray ◽  
X Ray Scattering ◽  
Scattering Study

AbstractSodium ion micro-solvated clusters, [Na(H2O) n]+, n = 1–7, were completed by (DFT) density functional theory at B3LYP/6-311+G(d,p) level in the gaseous phase. At the ambient situation, the four, five and six micro-solvated configurations can convert from each other. The investigation of the sequential water binding energy on Na+ obviously indicates that the influence of Na+ on the neighboring water molecules goes beyond the first solvation layer with the hydration number of 5. The hydration number of Na+ is 5 and the hydration space (rNa-O) is 2.43 Å. The current study displays that all our simulations have an brilliant harmony with the diffraction result from X-ray scattering study. The vibration frequency of H2O solvent was also determined. This work is important for additional identification of the Na+(H2O)n clusters in aqueous medium.

Electrochemistry, photoluminescence and theoretical study of the first 5,10,15,20-tetra-(4-(triazol-1-yl)phenyl) porphyridine complex

2018 ◽  
Vol 22 (04) ◽  
pp. 318-324
Author(s):  
Xiu-Guang Yi ◽  
Wen-Tong Chen ◽  
Jian-Gen Huang ◽  
Ding-Wa Zhang ◽  
Yin-Feng Wang
Keyword(s):  
Density Functional ◽  
Zinc Ion ◽  
Chloride Ions ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
Light Spectrum ◽  
Tetrahedral Geometry ◽  
Functional Theory ◽  
One Dimensional ◽  
X Ray

The first 5,10,15,20-tetra-(4-(triazol-1-yl)phenyl) porphyridine complex, [Zn[Formula: see text]Cl[Formula: see text](5,10,15,20-tetra-(4-(triazol-1-yl)phenyl)porphyridine)][Formula: see text]Cl•[Formula: see text]H[Formula: see text]O•7[Formula: see text]H[Formula: see text]O (1) has been synthesized via solvothermal reactions and characterized by single-crystal X-ray diffraction. Complex 1 is characteristic of a one-dimensional (1-D) structure, consisting of neutral [Zn[Formula: see text]Cl[Formula: see text](5,10,15,20-tetra-(4-(triazol-1-yl)phenyl) porphyridine)][Formula: see text] chains, isolated chloride ions and lattice water molecules. The zinc ion is in a four-coordinated tetrahedral geometry, and the porphyrin macrocycle is saddle-distorted. Photoluminescence measurement with solid-state samples discovers that it exhibits an emission in the green region of the light spectrum. Time-dependent density functional theory (TDDFT) calculation discovers that this emission can be attributed to the [Formula: see text]–[Formula: see text]* charge transfer. The cyclic voltammetry (CV) measurement reveals that it possesses an oxidation peak at 0.37 V.

scholarly journals X-ray diffraction and Density Functional Theory based structural analyses of 2-phenyl-4-(prop-2-yn-1-yl)-1,2,4-triazolone

2021 ◽  
Vol 12 (4) ◽  
pp. 459-468
Author(s):  
Shilpa Mallappa Somagond ◽  
Ahmedraza Mavazzan ◽  
Suresh Fakkirappa Madar ◽  
Madivalagouda Sannaikar ◽  
Shankar Madan Kumar ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Energy Gap ◽  
Basis Set ◽  
Frontier Molecular Orbital ◽  
Geometrical Parameters ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
X Ray

This study is composed of X-ray diffraction and Density Functional Theory (DFT) based molecular structural analyses of 2-phenyl-4-(prop-2-yn-1-yl)-2,4-dihydro-3H-1,2,4-triazol-3-one (2PPT). Crystal data for C11H9N3O: Monoclinic, space group P21/c (no. 14), a = 7.8975(2) Å, b = 11.6546(4) Å, c = 11.0648(3) Å, β = 105.212(2)°, V = 982.74(5) Å3, Z = 4, T = 296.15 K, μ(MoKα) = 0.091 mm-1, Dcalc = 1.346 g/cm3, 13460 reflections measured (5.174° ≤ 2Θ ≤ 64.72°), 3477 unique (Rint = 0.0314, Rsigma = 0.0298) which were used in all calculations. The final R1 was 0.0470 (I > 2σ(I)) and wR2 was 0.1368 (all data). The experimentally determined data was supported by theoretically optimized calculations processed with the help of Hartree-Fock (HF) technique and Density Functional Theory with the 6-311G(d,p) basis set in the ground state. Geometrical parameters (Bond lengths and angles) as well as spectroscopic (FT-IR, 1H NMR, and 13C NMR) properties of 2PPT molecule has been optimized theoretically and compared with the experimentally obtained results. Hirshfeld surface analysis with 2D fingerprinting plots was used to figure out the possible and most significant intermolecular interactions. The electronic characterizations such as molecular electrostatic potential map (MEP) and Frontier molecular orbital (FMO) energies have been studied by DFT/B3LYP approach. The MEP imparted the detailed information regarding electronegative and electropositive regions across the molecule. The HOMO-LUMO energy gap as high as 5.3601 eV was found to be responsible for the high kinetic stability of the 2PPT.

scholarly journals Molecular structure investigation by ab initio, DFT and X-ray diffraction of thiazole-derived compound

2014 ◽  
Vol 70 (a1) ◽  
pp. C1234-C1234
Author(s):  
Manel Boulakoud ◽  
Abdelkader Chouaih ◽  
Fodil Hamzaoui
Keyword(s):  
Molecular Structure ◽  
Density Functional Theory ◽  
Ab Initio ◽  
Density Functional ◽  
Intermolecular Hydrogen Bond ◽  
Basis Set ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
X Ray ◽  
Cell Parameters

We report here the synthesis of Z-3-(2-Ethoxyphenyl)-2-(2-Ethoxyphenyl)-1,3-Thiazolidin-4-one compound. The crystal structure has been determined by X-ray diffraction. The compound crystallizes in the monoclinic system with space group P21/n and cell parameters: a = 9.4094(10), b = 9.3066(10), c = 20.960(2) Å, β=99.0375(10)0, V = 1812.7(3)Å3 and Z = 4. The structure has been refined to a final R = 0.05 for 2083 observed reflections. The refined structure was found to be significantly non planar. The molecule exhibits intermolecular hydrogen bond of type C–H...O, C–H...N and C–H...S. Ab initio calculations were also performed at Hartree–Fock and density functional theory levels. The full HF and DFT geometry optimization was carried out using 6-31G(d,p) basis set. The observed molecular structure is compared with that calculated by both HF and density functional theory methods. The optimized geometry of the title compound was found to be consistent structure determined by X-ray diffraction.

scholarly journals Synthesis, Characterization, and Crystal Structure of N-(3-nitrophenyl)cinnamamide

Crystals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 599
Author(s):  
Jung-Seop Lee ◽  
Matthias Zeller ◽  
Shrikant Dashrath Warkad ◽  
Satish Balasaheb Nimse
Keyword(s):  
Crystal Structure ◽  
Density Functional ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
X Ray ◽  
Cell Dimensions ◽  
Atomic Scattering ◽  
Unit Cell Dimensions ◽  
Experimental Structure

N-(3-nitrophenyl)cinnamamide 1 with formula C15H12N2O3 was synthesized, and its crystal structure was determined by single-crystal X-ray diffraction analysis. Compound 1 crystallizes in the monoclinic space group P21/n with unit cell dimensions: a = 6.7810 (5) Å, b = 23.0913 (15) Å, c = 8.2079 (5) Å, V = 1282.76 (15) Å3, Z = 4, determined at 150 K with MoKα radiation. The experimental structure refined against atomic scattering factors is compared with the structure obtained using a Hirshfeld Atom Refinement (HAR) approach and Density Functional Theory (DFT) geometry optimizations.

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