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Updated: Jun 1, 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 monoclinic polymorph of cysteamine hydro-chloride.
Summary
The hydrochloride salt of cysteamine, a compound known as 2-mercaptoethan-aminium chloride, was found to crystallize in a monoclinic system. This crystal structure features a unique arrangement of cations and anions linked by hydrogen bonds, forming 2D networks.
Area of Science:
- Crystallography
- Solid-state chemistry
- Materials science
Background:
- Cysteamine hydrochloride (2-mercaptoethan-aminium chloride) is a significant chemical compound.
- Previous studies reported a triclinic polymorph of this salt.
- Understanding different crystalline forms is crucial for material properties.
Purpose of the Study:
- To investigate and characterize a new crystalline form of cysteamine hydrochloride.
- To determine the crystal system and structural features of this polymorph.
- To compare its structure with the previously reported triclinic form.
Main Methods:
- Single-crystal X-ray diffraction analysis.
- Crystallographic data collection and structure determination.
- Analysis of intermolecular interactions, including hydrogen bonding.
Main Results:
- The title compound, cysteamine hydrochloride, crystallized in the monoclinic crystal system.
- The crystal structure revealed cysteaminium cations linked to chloride anions by four hydrogen bonds (one S-H⋯Cl, three N-H⋯Cl).
- Two-dimensional slab-like networks were formed and stacked along the [100] direction, showing similarity to the triclinic polymorph.
Conclusions:
- A novel monoclinic polymorph of cysteamine hydrochloride has been successfully characterized.
- The hydrogen bonding network dictates the formation of 2D layered structures in the crystal.
- Structural similarities exist between the monoclinic and triclinic polymorphs, indicating potential phase relationships.
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