Bis(1,3-dimethyl-1H-imidazolium) hexa-fluoro-silicate methanol 0.33-solvate

Area of Science:

• Crystal Chemistry
• Supramolecular Chemistry
• Materials Science

Background:

• Crystallization of imidazolium salts with hexafluorosilicate anions (SiF6(2-)) can yield various solvatomorphs.
• Understanding the structural diversity and intermolecular interactions in these salts is crucial for materials design.

Purpose of the Study:

• To characterize the crystal structure of a novel methanol solvate of an imidazolium hexafluorosilicate salt.
• To elucidate the hydrogen bonding and packing arrangements within the crystal lattice.
• To investigate the formation and structural implications of solvatomorphism in this system.

Main Methods:

• Recrystallization of a crude imidazolium salt from methanol to obtain pure salt and solvatomorphs.
• Single-crystal X-ray diffraction to determine the crystal structure of the solvate (I) in space group P6/mcc.
• Analysis of crystallographic data to identify atomic positions, bond lengths, and intermolecular interactions (hydrogen bonds, F-H contacts).

Main Results:

• The title compound, 6C5H9N2(+)·3SiF6(2-)·CH3OH (I), was successfully synthesized and characterized.
• Crystal structure analysis revealed a rare hexagonal space group (P6/mcc) with a complex asymmetric unit.
• A detailed hydrogen bonding network was observed, involving imidazolium cations, hexafluorosilicate anions, and disordered methanol molecules, forming 1D rod-type ensembles and linked networks.

Conclusions:

• The study successfully characterized a novel imidazolium hexafluorosilicate methanol solvate, highlighting its unique crystal structure.
• The intricate hydrogen bonding network and the role of disordered solvent molecules were elucidated.
• The findings contribute to the understanding of solvatomorphism and crystal engineering of ionic compounds.