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Updated: May 31, 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
A second monoclinic polymorph of ethyl-enediammonium bis-(hydrogen squarate) monohydrate
Summary
A new crystal form of ethylenediamine bis-(hydrogen squarate) monohydrate was synthesized. This polymorph features a 3D framework built by hydrogen bonds between squarate anions, ethylenediamine, and water molecules.
Area of Science:
- Crystal Engineering
- Materials Science
- Supramolecular Chemistry
Background:
- Ethylenediamine bis-(hydrogen squarate) monohydrate is known to exhibit polymorphism.
- Understanding crystal structures and intermolecular interactions is crucial for materials design.
Purpose of the Study:
- To synthesize and characterize a new polymorph of ethylenediamine bis-(hydrogen squarate) monohydrate.
- To investigate the crystal structure and hydrogen bonding network of the new polymorph.
Main Methods:
- Synthesis via slow evaporation of an acid solution.
- X-ray crystallography to determine the asymmetric unit and crystal packing.
- Analysis of hydrogen bonding interactions (N-H⋯O, O-H⋯O).
Main Results:
- A new polymorph of ethylenediamine bis-(hydrogen squarate) monohydrate (C(2)H(10)N(2)·2HC(4)O(4)·H(2)O) was successfully synthesized.
- The crystal structure reveals a 3D framework formed by extensive hydrogen bonding.
- Very short intermolecular hydrogen bonds contribute to the cohesion between squarate groups.
- The new polymorph co-crystallized with a previously reported form.
Conclusions:
- The study reports a novel polymorph of ethylenediamine bis-(hydrogen squarate) monohydrate.
- The hydrogen bonding network plays a critical role in stabilizing the 3D crystal framework.
- The findings contribute to the understanding of polymorphism and crystal engineering in organic salts.
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