2-Amino-pyridin-1-ium triiodide
1Institut für Anorganische Chemie und Strukturchemie, Lehrstuhl II: Material- und Strukturforschung, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany.
Acta Crystallographica. Section E, Structure Reports Online
|September 19, 2013
Summary
This study details the crystal structure of 2-amino-pyridin-1-ium triiodide, revealing planar cations and triiodide anions. Hydrogen bonds form screwed chains, which twist into rods, showcasing unique crystal packing in this chemical compound.
Area of Science:
- Crystallography
- Solid-state chemistry
- Materials science
Background:
- Protonation of 2-aminopyridine can lead to various ionic structures.
- Triiodide anions are common counterions in halide salt chemistry.
- Understanding crystal packing influences material properties.
Purpose of the Study:
- To determine the crystal structure of 2-amino-pyridin-1-ium triiodide.
- To analyze the bonding and intermolecular interactions within the crystal.
- To describe the supramolecular arrangement of the compound.
Main Methods:
- Single-crystal X-ray diffraction was used to elucidate the crystal structure.
- Analysis of bond lengths, bond angles, and intermolecular distances.
- Hydrogen bond network analysis and crystal packing visualization.
Main Results:
- The asymmetric unit contains one 2-amino-pyridin-1-ium (apyH+) cation and one triiodide (I3-) anion.
- The apyH+ cation exhibits planarity with a short N-C bond typical of the imino form.
- Triiodide anion shows typical geometric parameters (bond lengths and angle).
- N-H ⋯ I hydrogen bonds link ions into screwed chains, forming pairwise twisted rectangular rods.
- Pyridinium rings in neighboring rods are parallel, with a plane-to-plane distance of 3.423 Å.
Conclusions:
- The crystal structure of 2-amino-pyridin-1-ium triiodide is characterized by specific ionic arrangements and hydrogen bonding.
- The observed crystal packing, involving screwed chains and rods, provides insight into supramolecular assembly.
- This structural information is crucial for understanding the chemical and physical properties of this compound.
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