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Updated: May 28, 2026
06:35
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
High-Z' and twinning behavior in 3,4-dinitrobenzoic acid
Matthias Zeller1, Jake L Stouffer, Virgil C Solomon
1Department of Chemistry, Youngstown State University, One University Plaza, Youngstown, OH 44555, USA. mzeller@ysu.edu
Summary
This study reveals complex crystal twinning and polymorphism in a nitro-substituted benzoic acid derivative. Six of eight possible molecular conformers were identified, with π-π stacking and O(nitro)···π interactions dominating crystal packing.
Area of Science:
- Crystallography
- Solid-state chemistry
- Molecular structure
Background:
- Understanding the solid-state structure of organic compounds is crucial for predicting their properties and applications.
- Nitro-substituted benzoic acid derivatives are important in various chemical fields, necessitating detailed structural analysis.
- Crystal twinning and polymorphism can significantly influence material properties.
Purpose of the Study:
- To elucidate the complex crystal structure of a specific nitro-substituted benzoic acid derivative (I).
- To investigate the factors governing molecular conformation and crystal packing in the solid state.
- To understand the nature of extensive non-merohedral twinning observed in the crystals.
Main Methods:
- Single-crystal X-ray diffraction analysis to determine the crystal structure and identify twinning.
- Analysis of molecular conformation, including tilt angles of nitro groups and protonation states.
- Computational methods, including force-field calculations and packing analysis, to assess intermolecular interactions.
Main Results:
- The compound crystallizes in the P1 space group with four molecules per asymmetric unit (Z'=4), exhibiting extensive non-merohedral twinning.
- Six distinct conformers out of eight theoretically possible conformers were identified in the solid-state structure.
- π-π stacking and O(nitro)···π interactions were found to be the dominant forces driving crystal packing, rather than hydrogen bonding.
Conclusions:
- The complex solid-state structure is characterized by significant molecular diversity (six conformers) and intricate twinning.
- Intermolecular π-π stacking and O(nitro)···π interactions play a critical role in stabilizing the observed crystal packing.
- The findings provide valuable insights into the structural complexity of nitro-substituted benzoic acid derivatives and factors influencing their solid-state organization.
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