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Published on: March 9, 2018
Redetermination of diammonium thio-molybdate.
Björn Hill1, Hans-Wolfram Lerner, Michael Bolte
1Institut für Anorganische Chemie der Goethe-Universität Frankfurt, Max-von-Laue-Strasse 7, D-60438 Frankfurt am Main, Germany.
Summary
This study determined the crystal structure of ammonium tetrathiomolybdate at 173 K, revealing hydrogen atom positions and a 3D network formed by N-H⋯S hydrogen bonds within the beta-K(2)SO(4) family.
Area of Science:
- Crystallography
- Solid-state chemistry
- Materials science
Background:
- Previous structure determinations of ammonium tetrathiomolybdate, (NH4)2[MoS4], did not fully localize hydrogen atom positions.
- The ammonium tetrathiomolybdate structure is known to belong to the beta-K(2)SO(4) family.
Purpose of the Study:
- To determine the crystal structure of ammonium tetrathiomolybdate at a lower temperature (173 K).
- To elucidate the precise positions of hydrogen atoms and the nature of intermolecular interactions.
Main Methods:
- Single-crystal X-ray diffraction at 173 K.
- Structure refinement to determine atomic positions.
Main Results:
- The crystal structure of (NH4)2[MoS4) was determined at 173 K, with hydrogen atom positions successfully localized.
- All ions were found to reside on crystallographic mirror planes.
- A three-dimensional network is formed by N-H⋯S hydrogen bonds, including bifurcated interactions.
- One nitrogen atom exhibits nine short contacts (<4 Å) to sulfur atoms, while the other shows ten.
Conclusions:
- The detailed crystal structure at 173 K provides a more complete understanding of ammonium tetrathiomolybdate.
- The identified hydrogen bonding network is crucial for the stability and properties of the material.
- This work refines the understanding of the beta-K(2)SO(4) structural family.
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