scholarly journals Crystal structure of the mineral strontiodresserite from laboratory powder diffraction data

2010 ◽  
Vol 25 (4) ◽  
pp. 322-328 ◽  
Author(s):  
P. S. Whitfield ◽  
L. D. Mitchell ◽  
Y. Le Page ◽  
J. Margeson ◽  
A. C. Roberts
Keyword(s):  
Crystal Structure ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Density Functional ◽  
Powder Diffraction Data ◽  
Hydrogen Atoms ◽  
Functional Theory ◽  
Space Group ◽  
Hydrogen Bond Networks ◽  
The Stability

The crystal structure of the mineral strontiodresserite, (Sr,Ca)Al2(CO3)2(OH)4⋅H2O, from the Francon Quarry, Montreal, Quebec, Canada, has been solved from laboratory powder diffraction data using a combination of charge-flipping and simulated annealing methods. The structure is orthorhombic in space group Pnma with a=16.0990(7), b=5.6133(3), and c=9.1804(4) Å (Z=4) and the framework of the mineral is isostructural with that of dundasite. The strontium has a coordination number of 9 and the carbonate anions form a bridge between the SrO9 polyhedra and AlO6 octahedra. The water molecule lies in a channel that runs parallel to the b axis. An ordered network of hydrogen atoms could be uniquely determined from crystal-chemical principles in the channels of strontiodresserite. Ab initio density functional theory (DFT) energy minimization of the whole structure gave results in full agreement with X-ray refinement results for nonhydrogen atoms. The stability of this model (as well as that of the corresponding model of dundasite) in the proposed Pnma space group was tested by DFT optimization in space group P1 of random small distortions of this structure. This test confirms that both minerals are isostructural, including their hydrogen-bond networks.

Crystal structure of citalopram hydrobromide, C20H22FN2OBr

2016 ◽  
Vol 31 (3) ◽  
pp. 176-184
Author(s):  
James A. Kaduk ◽  
Kai Zhong ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton
Keyword(s):  
Crystal Structure ◽  
Density Functional Theory ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Density Functional ◽  
Powder Diffraction Data ◽  
Powder Diffraction File ◽  
Functional Theory ◽  
X Ray ◽  
Van Der Waals Attraction

The crystal structure of citalopram hydrobromide has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional theory techniques. Citalopram hydrobromide crystallizes in space group P21/c (#14) with a = 10.766 45(6), b = 33.070 86(16), c = 10.892 85(5) Å, β = 90.8518(3)°, V = 3878.03(4) Å3, and Z = 8. N–H⋯Br hydrogen bonds are important to the structure, but the crystal energy is dominated by van der Waals attraction. The powder pattern was submitted to International Centre for Diffraction Data for inclusion in the Powder Diffraction File™.

scholarly journals Ab initio and DFT study on Cu (II) complex salicylate derivative

2014 ◽  
Vol 70 (a1) ◽  
pp. C1442-C1442
Author(s):  
Karthikeyan Natarajan ◽  
Sathya Duraisamy ◽  
Sivakumar Kandasamy
Keyword(s):  
Crystal Structure ◽  
Density Functional Theory ◽  
Single Crystal ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Density Functional ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
X Ray

X -ray diffraction becomes a routine process these decades for determining crystal structure of the materials. Most of the crystal structures solved nowadays is based on single crystal X-ray diffraction because it solves the crystal and molecular structures from small molecules to macro molecules without much human intervention. However it is difficult to grow single crystals of sufficient size and quality for conventional single-crystal X-ray diffraction studies. In such cases it becomes essential that structural information can be determined from powder diffraction data. With the recent developments in the direct-space approaches for structure solution, ab initio crystal structure analysis of molecular solids can be accomplished from X-ray powder diffraction data. It should be recalled that crystal structure determination from laboratory X-ray powder diffraction data is a far more difficult task than that of its single-crystal counterpart, particularly when the molecule possesses considerable flexibility or there are multiple molecules in the asymmetric unit. Salicylic acid and its derivatives used as an anti-inflammatory drug are known for its numerous medicinal applications. In our study, we synthesized mononuclear copper (II) complex of salicylate derivative. The structural characterization of the prepared compound was carried out using powder X-ray diffraction studies. Crystal structure of the compound has been solved by direct-space approach and refined by a combination of Rietveld method using TOPAS Academic V4.1. Density Functional Theory (DFT) calculations have to be carried in the solid state for the compound using GaussianW9.0 in the frame work of a generalized-gradient approximation (GGA). The geometry optimization was to be performed using B3LYP density functional theory. The atomic coordinates were taken from the final X-ray refinement cycle.

Crystal structure of bisoprolol fumarate Form I, (C18H32NO4) (C4H2O4)0.5

2019 ◽  
Vol 35 (1) ◽  
pp. 34-40
Author(s):  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Density Functional ◽  
Side Chain ◽  
Powder Diffraction Data ◽  
Powder Diffraction File ◽  
Space Group ◽  
X Ray

The crystal structure of bisoprolol fumarate Form I has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Bisoprolol fumarate Form I crystallizes in space group P-1 (#2) with a = 8.165 70(5) Å, b = 8.516 39(12) Å, c = 16.751 79(18) Å, α = 89.142(1)°, β = 78.155(1)°, γ = 81.763(1)°, V = 1128.265(10) Å3, and Z = 2. The neutral side chain of the bisoprolol cation is probably disordered. The cation and anion are linked by N–H⋯O and O–H⋯O hydrogen bonds. The cations are also linked by N–H⋯O hydrogen bonds. The result is alternating layers of hydrophilic and hydrophobic layers parallel to the ab-plane. The density of the structure is relatively low at 1.130 g cm−3, but there are no obvious voids in the structure. The powder pattern is included in the Powder Diffraction File™ as entry 00-066-1625.

Powder X-ray diffraction of varenicline hydrogen tartrate Form B (Chantix®), (C13H14N3)(HC4H4O6)

2021 ◽  
pp. 1-3
Author(s):  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Density Functional ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
Powder Diffraction File ◽  
Space Group ◽  
X Ray

The crystal structure of varenicline hydrogen tartrate Form B (Chantix®) has been refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Varenicline hydrogen tartrate Form B crystallizes in space group P212121 (#19) with a = 7.07616(2), b = 7.78357(2), c = 29.86149(7) Å, V = 1644.706(6) Å3, and Z = 4. The hydrogen bonds were identified and quantified. Hydrogen bonds link the cations and anions in zig-zag chains along the b-axis. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™ (PDF®).

scholarly journals Crystal Structure of Fosfomycin Tromethamine, (C4H12NO3)(C3H6O4P), from Synchrotron Powder Diffraction Data and Density Functional Theory

Crystals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 384 ◽  
Author(s):  
Zachary R. Butler ◽  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton
Keyword(s):  
Crystal Structure ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Density Functional ◽  
Powder Diffraction Data ◽  
Powder Diffraction File ◽  
Functional Theory ◽  
X Ray ◽  
Synchrotron Powder Diffraction ◽  
Methylene Groups

The crystal structure of fosfomycin tromethamine has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional techniques. Fosfomycin tromethamine crystallizes in space group P1 (#1) with a = 6.20421(6), b = 9.00072(7), c = 10.91257(15) Å, α = 93.4645(5), β = 101.9734(3), γ = 99.9183(2)°, V = 584.285(2) Å3, and Z = 2. A network of discrete hydrogen bonds links the cations and anions into layers parallel to the ab-plane. The outer surfaces of the layers are composed of the methyloxirane rings of the anions and the methylene groups of the cations. Furthermore, 93% of the atoms are consistent with an additional (pseudo)center of symmetry. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™.

Powder X-ray diffraction data for dimethylarsinic acid, (CH3)2AsO(OH)

2021 ◽  
pp. 1-6
Author(s):  
Joel W. Reid
Keyword(s):  
Crystal Structure ◽  
Diffraction Data ◽  
Density Functional ◽  
Dimethylarsinic Acid ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
Hydrogen Atoms ◽  
Functional Theory ◽  
X Ray ◽  
Synchrotron Powder Diffraction

Synchrotron powder diffraction data is presented for the monoclinic polymorph of dimethylarsinic acid, (CH3)2AsO(OH) (DMAV). Rietveld refinement with GSASII yielded lattice parameters of a = 15.9264(15) Å, b = 6.53999(8) Å, c = 11.3401(9) Å, and β = 125.8546(17)° (Z = 8, space group C2/c). The Rietveld-refined structure was compared with both a density functional theory (DFT)-optimized structure and the published, low-temperature single-crystal structure, and all three structures exhibited excellent agreement. The triclinic polymorph of DMAV was also DFT optimized with CRYSTAL17 to determine the positions of the hydrogen atoms. Monoclinic DMAV forms zigzag chains parallel to the b-axis with adjacent DMAV molecules connected by an O–H⋯O bond, whereas triclinic DMAV forms dimers connected by two O–H⋯O bonds.

Crystal structure of pomalidomide Form I, C13H11N3O4

2021 ◽  
pp. 1-6
Author(s):  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Powder Diffraction ◽  
Density Functional ◽  
Double Layers ◽  
Carbonyl Groups ◽  
Hydrogen Atoms ◽  
Powder Diffraction File ◽  
Functional Theory ◽  
Amine Hydrogen

The crystal structure of pomalidomide Form I has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional theory techniques. Pomalidomide Form I crystallizes in the space group P-1 (#2) with a = 7.04742(9), b = 7.89103(27), c = 11.3106(6) Å, α = 73.2499(13), β = 80.9198(9), γ = 88.5969(6)°, V = 594.618(8) Å3, and Z = 2. The crystal structure is characterized by the parallel stacking of planes parallel to the bc-plane. Hydrogen bonds link the molecules into double layers also parallel to the bc-plane. Each of the amine hydrogen atoms acts as a donor to a carbonyl group in an N–H⋯O hydrogen bond, but only two of the four carbonyl groups act as acceptors in such hydrogen bonds. Other carbonyl groups participate in C–H⋯O hydrogen bonds. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™ (PDF®).

Crystal structure of donepezil hydrochloride form III, C24H29NO3⋅HCl

2021 ◽  
pp. 1-8
Author(s):  
Joel W. Reid ◽  
James A. Kaduk
Keyword(s):  
Crystal Structure ◽  
Density Functional Theory ◽  
Powder Diffraction ◽  
Density Functional ◽  
Chloride Anion ◽  
Powder Diffraction Data ◽  
Powder Diffraction File ◽  
Functional Theory ◽  
Monoclinic Lattice ◽  
Donepezil Hydrochloride

The crystal structure of donepezil hydrochloride, form III, has been solved with FOX using laboratory powder diffraction data previously submitted to and published in the Powder Diffraction File. Rietveld refinement with GSAS yielded monoclinic lattice parameters of a = 14.3662(9) Å, b = 11.8384(6) Å, c = 13.5572(7) Å, and β = 107.7560(26)° (C24H30ClNO3, Z = 4, space group P21/c). The Rietveld-refined structure was compared to a density functional theory (DFT)-optimized structure, and the structures exhibit excellent agreement. Layers of donepezil molecules parallel to the (101) planes are maintained by columns of chloride anions along the b-axis, where each chloride anion hydrogen bonds to three donepezil molecules each.

scholarly journals Crystal structure of dilithium potassium citrate, Li2KC6H5O7 determined from powder diffraction data and DFT calculations

2019 ◽  
Vol 75 (3) ◽  
pp. 410-413 ◽  
Author(s):  
Andrew J. Cigler ◽  
James A. Kaduk
Keyword(s):  
Crystal Structure ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Density Functional ◽  
Potassium Citrate ◽  
Hydroxyl Group ◽  
Powder Diffraction Data ◽  
Coordination Polyhedra ◽  
Li Ion ◽  
Citrate Anion

The crystal structure of poly[μ-citrato-dilithium(I)potassium(I)], [Li2K(C6H5O7)] n , has been solved and refined using laboratory X-ray powder diffraction data, and optimized using density functional techniques. The citrate anion triply chelates to the K+ cation through the hydroxyl group, the central carboxylate, and the terminal carboxylate. The KO7 coordination polyhedra share edges, forming chains parallel to the a axis. These chains share edges with one tetrahedral Li ion, and are bridged by edge-sharing pairs of the second tetrahedral Li ion, forming layers parallel to the ac plane.

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