Two polymorphs of 2-ethyl-3-hydroxy-6-methylpyridinium hydrogen N-acetyl-L-glutamate from powder diffraction data
Vladimir V Chernyshev1, Sergey Y Efimov, Ksenia A Paseshnichenko
1Department of Chemistry, M.V. Lomonosov Moscow State University, 119991 Moscow, Russian Federation.
Acta Crystallographica. Section C, Crystal Structure Communications
|December 7, 2013
Summary
This study details the crystal structures of a title salt in monoclinic and orthorhombic forms, revealing distinct packing arrangements and hydrogen bonding networks in each polymorph.
Area of Science:
- Crystallography
- Materials Science
- Chemical Physics
Background:
- Polymorphism is crucial in determining the physical and chemical properties of crystalline solids.
- Understanding crystal structures aids in predicting material behavior and designing new compounds.
Purpose of the Study:
- To elucidate the crystal structures of the title salt in its monoclinic (M) and orthorhombic (O) polymorphic forms.
- To compare the crystal packing motifs and hydrogen bonding networks of the two polymorphs.
Main Methods:
- Laboratory powder diffraction data was utilized to establish the crystal structures.
- Analysis of hydrogen bonding interactions (N-H···O and O-H···O) and screw axes (21) informed the structural descriptions.
Main Results:
- Both monoclinic and orthorhombic polymorphs of the title salt were structurally characterized.
- Distinct crystal packing motifs were observed, with differences in anion arrangements and hydrogen bonding pathways.
- In the monoclinic form, anions form chains linked by hydrogen bonds, further organized into layers by cations.
- In the orthorhombic form, anions form helices linked by hydrogen bonds, with cations forming a 3D network.
Conclusions:
- The study successfully determined and compared the crystal structures of two polymorphs of the title salt.
- Differences in crystal packing and hydrogen bonding significantly distinguish the monoclinic and orthorhombic forms.
- The findings provide insights into the structural diversity and intermolecular interactions governing the solid-state behavior of this salt.
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