Crystal structures of two magnesium citrates from powder diffraction data.
1Department of Physics, North Central College, 131 S. Loomis, St., Naperville IL, 60540, USA.
Acta Crystallographica. Section E, Crystallographic Communications
|October 29, 2020
Summary
This study reveals the crystal structures of two magnesium citrate compounds. Researchers utilized synchrotron X-ray powder diffraction and density functional theory to analyze their atomic arrangements and bonding.
Area of Science:
- Crystallography
- Materials Science
- Inorganic Chemistry
Background:
- Magnesium citrate compounds are relevant in various applications.
- Understanding their crystal structures is key to predicting properties.
- Previous research exists on magnesium citrate decahydrate.
Purpose of the Study:
- To determine and refine the crystal structures of magnesium hydrogen citrate dihydrate and bis-(di-hydrogen citrato)magnesium.
- To investigate the coordination chemistry and hydrogen bonding in these magnesium citrate complexes.
- To compare the structural features of different magnesium citrate hydrates.
Main Methods:
- Synchrotron X-ray powder diffraction for crystal structure determination.
- Density functional theory for structural optimization.
- Analysis of coordination polyhedra and hydrogen bonding networks.
Main Results:
- The crystal structure of magnesium hydrogen citrate dihydrate (I) was solved, featuring a trans, trans-citrate anion triply chelating to Mg.
- The crystal structure of bis-(di-hydrogen citrato)magnesium (II) was solved, with a trans, gauche-citrate anion doubly chelating to Mg.
- Both compounds exhibit octahedral Mg cation coordination; isolated polyhedra in (I) and edge-sharing chains in (II). Strong O-H⋯O hydrogen bonds are present in both structures.
Conclusions:
- The distinct citrate conformations and coordination modes influence the resulting crystal structures.
- The observed hydrogen bonding patterns are crucial for structural stability.
- These findings provide detailed insights into magnesium citrate complex structures.
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