Tetra-quinolinium ditelluro(VI)octa-vanadate(V) octa-hydrate

Area of Science:

• Inorganic Chemistry
• Crystal Engineering
• Materials Science

Background:

• Heteropolyanions (HPAs) are versatile inorganic clusters with diverse structures and applications.
• Understanding the supramolecular assembly of HPAs with organic counterions is crucial for designing functional materials.

Purpose of the Study:

• To elucidate the crystal structure and supramolecular architecture of the (C9H8N)4[Te2V8O28]·8H2O compound.
• To investigate the role of quinolinium cations and water molecules in stabilizing the heteropolyanion framework through hydrogen bonding and π-π stacking.

Main Methods:

• Single-crystal X-ray diffraction was employed to determine the precise atomic arrangement and bonding in the title compound.
• Analysis of intermolecular interactions, including hydrogen bonds (N-H···O, O-H···O) and π-π stacking, was performed.

Main Results:

• The heteropolyanion [Te2V8O28]4- is generated around a crystallographic inversion center.
• Quinolinium cations engage in hydrogen bonding with both the polyoxidometallate framework and water molecules.
• Water molecules act as crucial linkers, forming hydrogen bonds within the structure.
• Aromatic π-π stacking interactions between quinolinium rings were observed, with a shortest centroid-centroid separation of 3.541(7) Å.

Conclusions:

• The investigated compound exhibits a complex three-dimensional network structure stabilized by a combination of hydrogen bonding and π-π stacking interactions.
• The interplay between the inorganic heteropolyanion, organic cations, and water molecules dictates the overall crystal packing and supramolecular assembly.
• This structural insight contributes to the broader understanding of designing and synthesizing novel polyoxometalate-based materials.