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Kenneth D. M. Harris - One of the best experts on this subject based on the ideXlab platform.
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Elucidating the Crystal Structure of dl-Arginine by Combined Powder X-Ray Diffraction Data Analysis and Periodic DFT-D Calculations
Crystal Growth & Design, 2017Co-Authors: Colan E. Hughes, Ines Boughdiri, Clément Bouakkaz, P. Andrew Williams, Kenneth D. M. HarrisAbstract:Among the 20 directly encoded proteinogenic amino acids, arginine is one of five remaining cases for which the crystal structure of a racemic crystalline phase has not yet been reported. In this paper, the crystal structure of dl-arginine is determined by exploiting modern methods for analysis of Powder X-Ray Diffraction data, in conjunction with periodic DFT-D calculations. The crystal structure of dl-arginine provides interesting contrasts and comparisons to that of the enantiomerically pure crystalline phase (l-arginine), which was also determined recently from Powder X-Ray Diffraction data.
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Combining the Advantages of Powder X-Ray Diffraction and NMR Crystallography in Structure Determination of the Pharmaceutical Material Cimetidine Hydrochloride
Crystal Growth & Design, 2016Co-Authors: Abigail E. Watts, Keisuke Maruyoshi, Colan E. Hughes, Steven P. Brown, Kenneth D. M. HarrisAbstract:We report the crystal structure of the anhydrous phase of cimetidine hydrochloride, determined directly from Powder X-Ray Diffraction data. The material was prepared by dehydration of the readily obtained monohydrate form of cimetidine hydrochloride, the only form for which a crystal structure has previously been reported. As such, solid-state dehydration processes typically yield the product phase as a microcrystalline Powder, and structure determination was carried out directly from Powder X-Ray Diffraction data, using the direct-space genetic algorithm technique for structure solution followed by Rietveld refinement. The structure determined from Powder X-Ray Diffraction was further validated by calculating solid-state 13C NMR data for the crystal structure (using first-principles periodic DFT techniques within the GIPAW approach) and assessing the quality of agreement with the corresponding experimental solid-state 13C CPMAS NMR data. This strategy provides a robust vindication of the correctness of t...
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Exploiting Powder X-Ray Diffraction for direct structure determination in structural biology: the P2X4 receptor trafficking motif YEQGL.
Journal of structural biology, 2011Co-Authors: Kotaro Fujii, Mark T. Young, Kenneth D. M. HarrisAbstract:We report the crystal structure of the 5-residue peptide acetyl-YEQGL-amide, determined directly from Powder X-Ray Diffraction data recorded on a conventional laboratory X-Ray Powder diffractometer. The YEQGL motif has a known biological role, as a trafficking motif in the C-terminus of mammalian P2X4 receptors. Comparison of the crystal structure of acetyl-YEQGL-amide determined here and that of a complex formed with the μ2 subunit of the clathrin adaptor protein complex AP2 reported previously, reveals differences in conformational properties, although there are nevertheless similarities concerning aspects of the hydrogen-bonding arrangement and the hydrophobic environment of the leucine sidechain. Our results demonstrate the potential for exploiting modern Powder X-Ray Diffraction methodology to achieve complete structure determination of materials of biological interest that do not crystallize as single crystals of suitable size and quality for single-crystal X-Ray Diffraction.
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Direct structure elucidation by Powder X-Ray Diffraction of a metal-organic framework material prepared by solvent-free grinding.
Chemical communications (Cambridge England), 2010Co-Authors: Kotaro Fujii, Zhigang Pan, Ana Lazuen Garay, Janeen Hill, Elena Sbircea, David C. Apperley, Stuart L. James, Kenneth D. M. HarrisAbstract:Powder X-Ray Diffraction (XRD) has been exploited to establish the structural properties of a porous interpenetrated mixed-ligand metal–organic framework material prepared by solid-state grinding, recognizing that product phases from mechanochemical synthesis are typically microcrystalline Powders. The importance of subjecting the Powder XRD data to rigorous scrutiny in such applications is emphasized.
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structure solution from Powder x ray Diffraction data by genetic algorithm techniques applied to organic materials generated as polycrystalline products from solid state processes
Materials and Manufacturing Processes, 2009Co-Authors: Kenneth D. M. HarrisAbstract:Many crystalline solids cannot be prepared as single crystals of sufficient size and quality to allow structure determination to be carried out using single crystal X-Ray Diffraction, and in such cases it is necessary to tackle structure determination using Powder X-Ray Diffraction. This article provides an overview of the direct-space genetic algorithm (GA) technique for solving crystal structures directly from Powder X-Ray Diffraction data, and illustrative examples are presented of the application of this technique in the structure determination of organic materials that can be obtained only by solid state processes that inherently generate polycrystalline products.
Catherine E. Housecroft - One of the best experts on this subject based on the ideXlab platform.
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Understanding the structural properties of a dendrimeric material directly from Powder X-Ray Diffraction data
The journal of physical chemistry. B, 2006Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, Catherine E. HousecroftAbstract:Complete structure determination of an early-generation dendrimeric material has been carried out directly from Powder X-Ray Diffraction data, using the direct-space genetic algorithm technique for structure solution followed by Rietveld refinement. This work represents the first application of modern direct-space techniques for structure determination from Powder X-Ray Diffraction data in the case of a dendrimeric material and paves the way for the future application of this approach to enable complete structure determination of other dendrimeric materials that cannot be prepared as single crystal samples suitable for single crystal X-Ray Diffraction studies.
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Solid-state structural properties of 2,4,6-trimethoxybenzene derivatives, determined directly from Powder X-Ray Diffraction data in conjunction with other techniques
Journal of Solid State Chemistry, 2006Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, James Alexis Platts, Catherine E. HousecroftAbstract:Structural properties of 2,4,6-trimethoxybenzaldehyde, 2,4,6-trimethoxybenzyl alcohol and 2,4,6-trimethoxyacetophenone have been determined directly from Powder X-Ray Diffraction data, using the direct-space Genetic Algorithm (GA) technique for structure solution followed by Rietveld refinement. Structural similarities and contrasts within this family of materials are elucidated. The work illustrates the value of utilizing information from other sources, including spectroscopic data and computational techniques, as a means of augmenting the structural knowledge established from the Powder X-Ray Diffraction data.
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A case study in direct-space structure determination from Powder X-Ray Diffraction data: Finding the hydrate structure of an organic molecule with significant conformational flexibility
Crystal Growth & Design, 2005Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, Catherine E. HousecroftAbstract:The structure of the monohydrate crystalline phase of 3,5-bis((3,4,5-trimethoxybenzyl)oxy)benzyl alcohol has been determined directly from Powder X-Ray Diffraction data using the direct-space genetic algorithm technique for structure solution followed by Rietveld refinement. This work raises several issues of a general nature concerning the assessment of results obtained in the structure determination of organic molecular solids from Powder X-Ray Diffraction data and serves as a case study that may find wider relevance in this field.
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Structural properties of methoxy derivatives of benzyl bromide, determined from Powder X-Ray Diffraction data
Powder Diffraction, 2005Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, Catherine E. HousecroftAbstract:Structure determination of 3,5-dimethoxybenzyl bromide and 3,4,5-trimethoxybenzyl bromide has been carried out from laboratory Powder X-Ray Diffraction data using the direct-space Genetic Algorithm technique for structure solution followed by Rietveld refinement. These two compounds are of interest for their potential use as building blocks for the synthesis of dendritic materials. Although the two molecules differ only in the presence/absence of the methoxy group at the 4-position of the aromatic ring, the structural properties of the two materials are significantly different
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Structural Aspects of a Dendrimer Precursor Determined Directly from Powder X-Ray Diffraction Data
Crystal Growth & Design, 2004Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, Catherine E. HousecroftAbstract:The structure of 3,5-dimethoxybenzyl alcohol has been determined directly from Powder X-Ray Diffraction data using the genetic algorithm technique for structure solution followed by Rietveld refinement. This material is the precursor to a family of dendrimer materials, and structural features exhibited by 3,5-dimethoxybenzyl alcohol in the solid state may be important in the rationalization of higher generation dendrimer materials within this family.
Zhigang Pan - One of the best experts on this subject based on the ideXlab platform.
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Direct structure elucidation by Powder X-Ray Diffraction of a metal-organic framework material prepared by solvent-free grinding.
Chemical communications (Cambridge England), 2010Co-Authors: Kotaro Fujii, Zhigang Pan, Ana Lazuen Garay, Janeen Hill, Elena Sbircea, David C. Apperley, Stuart L. James, Kenneth D. M. HarrisAbstract:Powder X-Ray Diffraction (XRD) has been exploited to establish the structural properties of a porous interpenetrated mixed-ligand metal–organic framework material prepared by solid-state grinding, recognizing that product phases from mechanochemical synthesis are typically microcrystalline Powders. The importance of subjecting the Powder XRD data to rigorous scrutiny in such applications is emphasized.
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Vapour Induced Crystalline Transformation Investigated by ab initio Powder X-Ray Diffraction Analysis
Crystal Growth & Design, 2009Co-Authors: Kotaro Fujii, Hidehiro Uekusa, Zhigang Pan, Yasunari Ashida, Shinya Hirano, Shinji Toyota, Fumio Toda, Kenneth D. M. HarrisAbstract:A new co-crystal (phase H) of 5-methyl-2-pyridone (5MP) and trimesic acid (TMA) has been prepared by grinding a methanol solvate co-crystal (phase M) of 5MP and TMA under ambient conditions. Powder X-Ray Diffraction indicates that the new co-crystal phase H is structurally different from the methanol solvate co-crystal (phase M) and an unsolvated co-crystal (phase U) of 5MP and TMA reported previously. In the present work, the crystal structure of the new phase H has been determined directly from Powder X-Ray Diffraction data, allowing insights to be gained regarding the mechanism of the transformation from M to H. The structural analysis reveals that phase H is a hydrate of 5MP and TMA, and thus the transformation from M to H is a solvent exchange process. The rate of this process is shown to be accelerated significantly by grinding. Further vapour induced transformations have been investigated for phases M, H, and U, and insights regarding transformation mechanisms have been established from considerati...
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Understanding the structural properties of a dendrimeric material directly from Powder X-Ray Diffraction data
The journal of physical chemistry. B, 2006Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, Catherine E. HousecroftAbstract:Complete structure determination of an early-generation dendrimeric material has been carried out directly from Powder X-Ray Diffraction data, using the direct-space genetic algorithm technique for structure solution followed by Rietveld refinement. This work represents the first application of modern direct-space techniques for structure determination from Powder X-Ray Diffraction data in the case of a dendrimeric material and paves the way for the future application of this approach to enable complete structure determination of other dendrimeric materials that cannot be prepared as single crystal samples suitable for single crystal X-Ray Diffraction studies.
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Solid-state structural properties of 2,4,6-trimethoxybenzene derivatives, determined directly from Powder X-Ray Diffraction data in conjunction with other techniques
Journal of Solid State Chemistry, 2006Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, James Alexis Platts, Catherine E. HousecroftAbstract:Structural properties of 2,4,6-trimethoxybenzaldehyde, 2,4,6-trimethoxybenzyl alcohol and 2,4,6-trimethoxyacetophenone have been determined directly from Powder X-Ray Diffraction data, using the direct-space Genetic Algorithm (GA) technique for structure solution followed by Rietveld refinement. Structural similarities and contrasts within this family of materials are elucidated. The work illustrates the value of utilizing information from other sources, including spectroscopic data and computational techniques, as a means of augmenting the structural knowledge established from the Powder X-Ray Diffraction data.
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A case study in direct-space structure determination from Powder X-Ray Diffraction data: Finding the hydrate structure of an organic molecule with significant conformational flexibility
Crystal Growth & Design, 2005Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, Catherine E. HousecroftAbstract:The structure of the monohydrate crystalline phase of 3,5-bis((3,4,5-trimethoxybenzyl)oxy)benzyl alcohol has been determined directly from Powder X-Ray Diffraction data using the direct-space genetic algorithm technique for structure solution followed by Rietveld refinement. This work raises several issues of a general nature concerning the assessment of results obtained in the structure determination of organic molecular solids from Powder X-Ray Diffraction data and serves as a case study that may find wider relevance in this field.
Eugene Y. Cheung - One of the best experts on this subject based on the ideXlab platform.
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Understanding the structural properties of a dendrimeric material directly from Powder X-Ray Diffraction data
The journal of physical chemistry. B, 2006Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, Catherine E. HousecroftAbstract:Complete structure determination of an early-generation dendrimeric material has been carried out directly from Powder X-Ray Diffraction data, using the direct-space genetic algorithm technique for structure solution followed by Rietveld refinement. This work represents the first application of modern direct-space techniques for structure determination from Powder X-Ray Diffraction data in the case of a dendrimeric material and paves the way for the future application of this approach to enable complete structure determination of other dendrimeric materials that cannot be prepared as single crystal samples suitable for single crystal X-Ray Diffraction studies.
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Solid-state structural properties of 2,4,6-trimethoxybenzene derivatives, determined directly from Powder X-Ray Diffraction data in conjunction with other techniques
Journal of Solid State Chemistry, 2006Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, James Alexis Platts, Catherine E. HousecroftAbstract:Structural properties of 2,4,6-trimethoxybenzaldehyde, 2,4,6-trimethoxybenzyl alcohol and 2,4,6-trimethoxyacetophenone have been determined directly from Powder X-Ray Diffraction data, using the direct-space Genetic Algorithm (GA) technique for structure solution followed by Rietveld refinement. Structural similarities and contrasts within this family of materials are elucidated. The work illustrates the value of utilizing information from other sources, including spectroscopic data and computational techniques, as a means of augmenting the structural knowledge established from the Powder X-Ray Diffraction data.
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A case study in direct-space structure determination from Powder X-Ray Diffraction data: Finding the hydrate structure of an organic molecule with significant conformational flexibility
Crystal Growth & Design, 2005Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, Catherine E. HousecroftAbstract:The structure of the monohydrate crystalline phase of 3,5-bis((3,4,5-trimethoxybenzyl)oxy)benzyl alcohol has been determined directly from Powder X-Ray Diffraction data using the direct-space genetic algorithm technique for structure solution followed by Rietveld refinement. This work raises several issues of a general nature concerning the assessment of results obtained in the structure determination of organic molecular solids from Powder X-Ray Diffraction data and serves as a case study that may find wider relevance in this field.
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Structural properties of methoxy derivatives of benzyl bromide, determined from Powder X-Ray Diffraction data
Powder Diffraction, 2005Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, Catherine E. HousecroftAbstract:Structure determination of 3,5-dimethoxybenzyl bromide and 3,4,5-trimethoxybenzyl bromide has been carried out from laboratory Powder X-Ray Diffraction data using the direct-space Genetic Algorithm technique for structure solution followed by Rietveld refinement. These two compounds are of interest for their potential use as building blocks for the synthesis of dendritic materials. Although the two molecules differ only in the presence/absence of the methoxy group at the 4-position of the aromatic ring, the structural properties of the two materials are significantly different
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Rationalizing the structural properties of bupivacaine base—A local anesthetic—directly from Powder X‐ray Diffraction data
Journal of pharmaceutical sciences, 2004Co-Authors: Eugene Y. Cheung, Kenneth D. M. Harris, Roy L. Johnston, Simon J. Kitchin, Kelly L. Hadden, Marek ZakrzewskiAbstract:Bupivacaine belongs to a family of 1-alkyl-2',6'-pipecoloxylidides, which has shown promise as reversible action potential blockers that can introduce prolonged local anesthetic effects. The crystal structure of the free-base form of bupivacaine has been determined directly from Powder X-Ray Diffraction data using the Genetic Algorithm technique for structure solution, followed by Rietveld refinement. This work further emphasizes the scope and utility of ab initio structure solution directly from Powder X-Ray Diffraction data for tackling structural problems within the biomedical field, leading to opportunities for the investigation of structure-property relationships.
Edwin C. Constable - One of the best experts on this subject based on the ideXlab platform.
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Understanding the structural properties of a dendrimeric material directly from Powder X-Ray Diffraction data
The journal of physical chemistry. B, 2006Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, Catherine E. HousecroftAbstract:Complete structure determination of an early-generation dendrimeric material has been carried out directly from Powder X-Ray Diffraction data, using the direct-space genetic algorithm technique for structure solution followed by Rietveld refinement. This work represents the first application of modern direct-space techniques for structure determination from Powder X-Ray Diffraction data in the case of a dendrimeric material and paves the way for the future application of this approach to enable complete structure determination of other dendrimeric materials that cannot be prepared as single crystal samples suitable for single crystal X-Ray Diffraction studies.
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Solid-state structural properties of 2,4,6-trimethoxybenzene derivatives, determined directly from Powder X-Ray Diffraction data in conjunction with other techniques
Journal of Solid State Chemistry, 2006Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, James Alexis Platts, Catherine E. HousecroftAbstract:Structural properties of 2,4,6-trimethoxybenzaldehyde, 2,4,6-trimethoxybenzyl alcohol and 2,4,6-trimethoxyacetophenone have been determined directly from Powder X-Ray Diffraction data, using the direct-space Genetic Algorithm (GA) technique for structure solution followed by Rietveld refinement. Structural similarities and contrasts within this family of materials are elucidated. The work illustrates the value of utilizing information from other sources, including spectroscopic data and computational techniques, as a means of augmenting the structural knowledge established from the Powder X-Ray Diffraction data.
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A case study in direct-space structure determination from Powder X-Ray Diffraction data: Finding the hydrate structure of an organic molecule with significant conformational flexibility
Crystal Growth & Design, 2005Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, Catherine E. HousecroftAbstract:The structure of the monohydrate crystalline phase of 3,5-bis((3,4,5-trimethoxybenzyl)oxy)benzyl alcohol has been determined directly from Powder X-Ray Diffraction data using the direct-space genetic algorithm technique for structure solution followed by Rietveld refinement. This work raises several issues of a general nature concerning the assessment of results obtained in the structure determination of organic molecular solids from Powder X-Ray Diffraction data and serves as a case study that may find wider relevance in this field.
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Structural properties of methoxy derivatives of benzyl bromide, determined from Powder X-Ray Diffraction data
Powder Diffraction, 2005Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, Catherine E. HousecroftAbstract:Structure determination of 3,5-dimethoxybenzyl bromide and 3,4,5-trimethoxybenzyl bromide has been carried out from laboratory Powder X-Ray Diffraction data using the direct-space Genetic Algorithm technique for structure solution followed by Rietveld refinement. These two compounds are of interest for their potential use as building blocks for the synthesis of dendritic materials. Although the two molecules differ only in the presence/absence of the methoxy group at the 4-position of the aromatic ring, the structural properties of the two materials are significantly different
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Structural Aspects of a Dendrimer Precursor Determined Directly from Powder X-Ray Diffraction Data
Crystal Growth & Design, 2004Co-Authors: Zhigang Pan, Eugene Y. Cheung, Kenneth D. M. Harris, Edwin C. Constable, Catherine E. HousecroftAbstract:The structure of 3,5-dimethoxybenzyl alcohol has been determined directly from Powder X-Ray Diffraction data using the genetic algorithm technique for structure solution followed by Rietveld refinement. This material is the precursor to a family of dendrimer materials, and structural features exhibited by 3,5-dimethoxybenzyl alcohol in the solid state may be important in the rationalization of higher generation dendrimer materials within this family.
