X-ray powder diffraction analysis of abacavir hemisulfate

2005 ◽  
Vol 20 (3) ◽  
pp. 241-245 ◽  
Author(s):  
Gerald Monger ◽  
Peter Varlashkin
Keyword(s):  
Reverse Transcriptase ◽  
Diffraction Analysis ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Internal Standard ◽  
Unit Cell ◽  
Powder Pattern ◽  
Hiv Reverse Transcriptase ◽  
X Ray ◽  
Anti Hiv

The room temperature powder pattern of abacavir hemisulfate (anti-HIV reverse transcriptase compound) was indexed using 2θ values obtained from a powder pattern spiked with an internal standard. The resulting unit cell values for the monoclinic I2 cell [nonstandard setting of C2 (No. 5)] are a=13.278(1) Å, b=8.437(1) Å, c=14.259(2) Å, β=93.87(1)°. There are two formula units [(C14H16N6O)2.H2SO4] per unit cell and Dx=1.390 g∕cm3.

X-ray powder diffraction analysis of ±-fenoprofen calcium dihydrate

2002 ◽  
Vol 17 (3) ◽  
pp. 244-246
Author(s):  
Ailette Aguila Tobien ◽  
Peter Varlashkin
Keyword(s):  
Single Crystal ◽  
Diffraction Analysis ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Unit Cell ◽  
Powder Pattern ◽  
Crystal Data ◽  
Racemic Compound ◽  
Internal Standards ◽  
X Ray

The current JCPDS powder pattern for the racemic compound fenoprofen calcium dihydrate (card No. 44-1790) is unindexed. Previously we reported the single crystal data, determined at −100 °C, for this material (Zhu et al., 2001). Using 2θ values obtained from a powder pattern spiked with internal standards, we indexed the room temperature powder pattern. The resulting unit cell values for the monoclinic P21/n cell are a=19.018 Å, b=7.738 Å, c=19.472 Å, β=91.66°.

X-ray powder diffraction analysis of 2-exo-(β-pyridyl)-6-exo-phenyl-7-oxa-1-azabicyclo[2.2.1]heptane

2003 ◽  
Vol 18 (1) ◽  
pp. 47-49
Author(s):  
J. C. Poveda ◽  
J. A. Henao ◽  
J. A. Pinilla ◽  
V. V. Kouznetsov ◽  
C. Ochoa
Keyword(s):  
Diffraction Analysis ◽  
Diffraction Pattern ◽  
Powder Diffraction ◽  
Heterocyclic System ◽  
Unit Cell ◽  
Unit Cell Parameters ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters

The X-ray powder diffraction pattern for a bridgehead heterocyclic system was determined. 2-exo-(β-pyridyl)-6-exo-phenyl-7-oxa-1-azabicyclo[2.2.1]heptane, C16H16N2O, is triclinic with refined unit cell parameters a=1.1012(2), b=1.3950(2), c=1.0074(3) nm, α=111.09(2)°, β=104.97(2)°, γ=77.38(2)°, V=1.3813(3) nm3, Z=4, and Dx=1.212 g/cm3 with space group P-1 (No. 2).

scholarly journals Powder X-ray diffraction of trimethoprim Form I, C14H18N4O3

2020 ◽  
Vol 35 (1) ◽  
pp. 69-70
Author(s):  
Jerry Hong ◽  
Joseph T. Golab ◽  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton
Keyword(s):  
Powder Diffraction ◽  
Diffraction Data ◽  
Room Temperature ◽  
The United States ◽  
Unit Cell ◽  
Cell Length ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure Determinations ◽  
Unit Cell Length

Trimethoprim crystallizes in the triclinic space group P-1 (#2) with a = 10.5085(3), b = 10.5417(2), c = 8.05869(13) Å, α = 101.23371(21), β = 112.1787(3), γ = 112.6321(4)°, V = 743.729 Å3, and Z = 2. A reduced cell search in the Cambridge Structural Database yielded three previous structure determinations, using data collected at 100 K, 173 K, and room temperature. In this work, the sample was ordered from the United States Pharmacopeial Convention (USP) and analyzed as-received. The room temperature (295 K) crystal structure was refined using synchrotron (λ = 0.412826 Å) powder diffraction data and optimized using density functional theory techniques. We found similar hydrogen bonding patterns with the previous determinations. In addition, we identified two C–H⋯O hydrogen bonds, which also contribute to the crystal energy. When comparing the previously reported trimethoprim structure determinations, the unit cell length lattice parameters were found to contract at lower temperatures, particularly 100 K. All structures show reasonable agreement, with unit cell length differences ranging between 0.05 and 0.15 Å. The diffraction data for this study were collected on beamline 11-BM at the Advanced Photon Source, and the powder X-ray diffraction pattern of the compound has been submitted to ICDD® for inclusion in the Powder Diffraction File™ (PDF®).

X-ray powder diffraction data for compound DyNiSn

1997 ◽  
Vol 12 (3) ◽  
pp. 134-135
Author(s):  
Liangqin Nong ◽  
Lingmin Zeng ◽  
Jianmin Hao
Keyword(s):  
Powder Diffraction ◽  
Diffraction Data ◽  
Figure Of Merit ◽  
Room Temperature ◽  
Unit Cell ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Diffraction Patterns

The compound DyNiSn has been studied by X-ray powder diffraction. The X-ray diffraction patterns for this compound at room temperature are reported. DyNiSn is orthorhombic with lattice parameters a=7.1018(1) Å, b=7.6599(2) Å, c=4.4461(2) Å, space group Pna21 and 4 formula units of DyNiSn in unit cell. The Smith and Snyder Figure-of-Merit F30 for this powder pattern is 26.7(0.0178,63).

X-ray powder diffraction analysis of the heteropoly-molybdate (MoO2)0.5PMo14O42

2003 ◽  
Vol 18 (3) ◽  
pp. 236-239 ◽  
Author(s):  
L. Marosi ◽  
J. Cifré ◽  
C. Otero Areán
Keyword(s):  
Catalytic Activity ◽  
Diffraction Analysis ◽  
Computer Modeling ◽  
Powder Diffraction ◽  
Rietveld Analysis ◽  
Nitrogen Atmosphere ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Patterns

The new heteropoly blue compound (MoO2)0.5PMo14O42, which is relevant in the context of catalytic activity of heteropoly-molybdates, was prepared by controlled thermolysis of (NH4)3PMo12O40 at 730 K in a nitrogen atmosphere. Powder X-ray diffraction analysis showed that this compound has a cubic unit cell, space group Pn3m (No. 224), with ao=11.795(2) Å, Z=2 and DXR=4.2466 g cm−3. Computer modeling and Rietveld analysis of powder diffraction patterns led to a proposed structure of the corresponding Keggin-cage unit PMo14O42.

X-ray diffraction analysis of (Na0.6H0.4)(Ta0.7Nb0.3)O3

1999 ◽  
Vol 14 (3) ◽  
pp. 231-233 ◽  
Author(s):  
Raj P. Singh ◽  
Michael J. Miller ◽  
Jeffrey N. Dann
Keyword(s):  
High Temperature ◽  
Diffraction Analysis ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Unit Cell ◽  
Type Structure ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
X Ray

(Na0.6H0.4)(Ta0.7Nb0.3)O3 was synthesized by heating a tantalum/niobium scale containing two sodium tantalate/niobate phases :Na14(Ta0.7Nb0.3)12O37·31H2O and NaH2Ta0.7Nb0.3O4. Powder X-ray diffraction data for (Na0.6H0.4)(Ta0.7Nb0.3)O3 indicated it to be a cubic perovskite (ABO3/ReO3 type structure) with unit cell a0=3.894 Å. The compound is analogous to the mineral lueshite (NaNbO3), and to the high temperature forms of NaTaO3 and NaNbO3. Powder diffraction data for (Na0.6H0.4)(Ta0.7Nb0.3)O3 will be useful in the analysis of synthetic tantalum/niobium concentrates.

X-ray powder diffraction data of anilinium trimolybdate tetrahydrate and anilinium trimolybdate dihydrate

1999 ◽  
Vol 14 (4) ◽  
pp. 280-283 ◽  
Author(s):  
A. Rafalska-Łasocha ◽  
W. Łasocha ◽  
M. Michalec
Keyword(s):  
Powder Diffraction ◽  
Diffraction Data ◽  
Room Temperature ◽  
Unit Cell ◽  
Powder Diffraction Data ◽  
Unit Cell Parameters ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
Diffraction Patterns

The X-ray powder diffraction patterns of anilinium trimolybdate tetrahydrate, (C6H5NH3)2Mo3O10·4H2O, and anilinium trimolybdate dihyhydrate, (C6H5NH3)2Mo3O10·2H2O, have been measured in room temperature. The unit cell parameters were refined to a=11.0670(7) Å, b=7.6116(8) Å, c=25.554(3) Å, space group Pnma(62) and a=17.560(2) Å, b=7.5621(6) Å, c=16.284(2) Å, β=108.54(1)°, space group P21(4) or P21/m(11) for orthorhombic anilinium trimolybdate tetrahydrate and monoclinic anilinium trimolybdate dihydrate, respectively.

scholarly journals Phase transitions in efavirenz induced by mechanical activation

2014 ◽  
Vol 70 (a1) ◽  
pp. C1565-C1565
Author(s):  
Alcemira Oliveira ◽  
Alejandro Ayala
Keyword(s):  
Thermal Analysis ◽  
Reverse Transcriptase ◽  
Room Temperature ◽  
Experimental Methodology ◽  
Reverse Transcriptase Inhibitors ◽  
Nucleoside Reverse Transcriptase Inhibitors ◽  
Scientific Publications ◽  
X Ray ◽  
Crystalline Forms ◽  
Anti Hiv

Efavirenz,(S)-6-chloro-4(cyclopropylethynyl)-1,4-dihydro-4-(trifluoromethyl)-2H-3,1-benzoxazin-2-one, is a anti HIV agent belonging to the class of the non-nucleoside reverse transcriptase inhibitors, which is used in combination with other protease inhibitors or nucleoside reverse transcriptase inhibitors. Several polymorphs were reported in patents and scientific publications, being form I the thermodynamically most stable and the selected for commercial formulations. Mechanochemistry has emerged as an experimental methodology to efficiently and rapidly screen for new solid forms of a pharmaceutical active ingredient. These methods include neat and drop assisted grinding have been successfully applied to produce solvates, polymorphs, salts and cocrystals. In this contribution, we investigate the structural stability of efavirenz under mechanochemistry conditions. Room temperature and cryogenic neat and drop assisted grinding were applied to induce new crystalline forms, which were characterized by x-ray powder diffraction, vibrational spectroscopy and thermal analysis. The mechanism involved in these transformations were also investigated and discussed.

X-ray powder diffraction investigation of new high temperature polymorphs of CaTeO3 and CaTe2O5

2001 ◽  
Vol 16 (4) ◽  
pp. 205-211 ◽  
Author(s):  
S. N. Tripathi ◽  
R. Mishra ◽  
M. D. Mathews ◽  
P. N. Namboodiri
Keyword(s):  
High Temperature ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Solid Phase ◽  
High Temperature Phase ◽  
Unit Cell ◽  
Stable Phase ◽  
Temperature Phase ◽  
X Ray ◽  
Monoclinic Lattice

X-ray powder diffraction investigation of the new high temperature polymorphs beta- and gamma-CaTeO3 and gamma- and delta-CaTe2O5 and picnometric measurements of the room temperature phases of the two compounds have been carried out. The study led to the elucidation of their unit cell structures and assignment of entirely new lattice types and parameters to the room temperature phases of CaTeO3 and CaTe2O5 in contrast and supersession to the existing structural information. The results are as follows: CaTeO3 has only one stable phase at room temperature and temperatures up to 882 °C, i.e., α- and has a triclinic unit cell with a=4.132±0.003 Å, b=6.120±0.006 Å, c=12.836±0.013 Å, α=121.80°, β=99.72°, γ=97.26°. The first high temperature phase stable between 882 and 894 °C, i.e., β-CaTeO3, has a monoclinic lattice: a=20.577±0.007 Å, b=21.857±0.009 Å, c=4.111±0.002 Å, β=96.15°, while the next phase stable above 894 °C, i.e., γ-CaTeO3, has a hexagonal unit cell with parameters: a=14.015±0.0001 Å, c=9.783±0.001 Å, c/a=0.698. CaTe2O5 has one stable phase at temperatures up to 802 °C, i.e., α-CaTe2O5 with a monoclinic lattice and parameters: a=9.069±0.002 Å, b=25.175±0.007 Å, c=3.366±0.001 Å, β=98.29 °. The first high temperature phase stable in the range 802–845°, i.e., β-CaTe2O5, is monoclinic with unit cell parameters: a=4.146±0.001 Å, b=5.334±0.002 Å, c=6.105±0.002 Å, β=98.362 °; the next higher temperature phase stable over 845–857 °C, i.e., γ-CaTe2O5, has an orthorhombic unit cell with: a=8.638±0.001 Å, b=9.291±0.001 Å, c=7.862±0.001 Å and the highest temperature solid phase stable above 857 °C, i.e., δ-CaTe2O5 has a tetragonal unit cell with a=5.764±0.000 Å, c=32.074±0.020 Å, c/a=5.5637.

Notizen: Preparation and Crystal Structure of NiHg

1977 ◽  
Vol 32 (4) ◽  
pp. 479 ◽  
Author(s):  
M. Pušelj ◽  
Z. Ban
Keyword(s):  
Crystal Structure ◽  
Diffraction Analysis ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Single Phase ◽  
Extended Period ◽  
Structure Type ◽  
X Ray

A single phase binary amalgam of the composition NiHg was found to form at room temperature after an extended period of time (approx. 2 years).X-ray powder diffraction analysis enabled us to determine the crystal structure. The compound crystallizes tetragonally with a = 4.22 Å and c = 3.14 Å. It belongs to L 10 crystal structure type.

Sign in / Sign up

Export Citation Format

Share Document