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Updated: Jan 18, 2026
11:10
Atomic Layer Deposition of Vanadium Dioxide and a Temperature-dependent Optical Model
Published on: May 23, 2018
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The crystal structure of a spherical vanadium complex encapsulating a nitrate anion
Rian Jordaan1, Christo van Staden1, Dumisani V Kama1
1University of the Free State, Chemistry Department, Bloemfontein, South Africa.
Acta Crystallographica. Section E, Crystallographic Communications
|September 8, 2025
Summary
Researchers report the crystal structure of a novel nitrate-vanadium-oxygen complex. This complex features a spherical vanadium-oxygen structure encasing a nitrate anion, stabilized by sodium hydroxy and water molecules.
Area of Science:
- Inorganic Chemistry
- Crystal Engineering
- Materials Science
Background:
- Vanadium-oxygen clusters are known for their diverse structural motifs and potential applications.
- Nitrate anions can act as templates or structural components in coordination compounds.
- Understanding supramolecular assembly in metal-oxygen frameworks is crucial for designing new materials.
Purpose of the Study:
- To determine and report the detailed crystal structure of a novel nitrate-caged vanadium-oxygen complex.
- To investigate the coordination environments of vanadium and sodium ions within the crystal lattice.
- To analyze the role of hydrogen bonding and inter-sheet interactions in molecular packing.
Main Methods:
- Single-crystal X-ray diffraction was employed to elucidate the complex's three-dimensional structure.
- Analysis of crystallographic data to identify coordination geometries and bonding interactions.
- Characterization of the non-centrosymmetric crystal system (Cc space group).
Main Results:
- The crystal structure reveals a spherical vanadium-oxygen framework encapsulating a nitrate anion.
- The complex contains both vanadium(IV) and vanadium(V) oxidation states, with octahedral coordination.
- Sodium ions and sodium hydroxy groups are located externally, exhibiting variable coordination numbers (5-8) and geometries, contributing to the overall molecular packing through interactions with the vanadium sphere.
Conclusions:
- The reported structure represents a unique example of a nitrate anion templated within a vanadium-oxygen sphere.
- The interplay between the spherical vanadium-oxygen core, sodium hydroxy sheets, and solvent molecules dictates the crystal packing.
- This study contributes to the understanding of complex inorganic structures and potential self-assembly mechanisms.
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