Cs[H2NB2(C6F5)6] Featuring an Unequivocal 16-Coordinate Cation

Area of Science:

• Inorganic Chemistry
• Coordination Chemistry
• Materials Science

Background:

• Development of novel compounds with unique coordination environments.
• Need for effective cesium removal agents in nuclear waste management and medical applications.

Purpose of the Study:

• Synthesize and characterize cesium bis(perfluoro-triphenylborane)amide (Cs[H2NB2(C6F5)6]).
• Investigate the coordination behavior of the [H2NB2(C6F5)6](-) anion and the Cs(+) cation.
• Explore potential applications of the synthesized compound.

Main Methods:

• Chemical synthesis involving sodium salt and CsF.
• Molecular structure determination using X-ray crystallography.
• Solubility studies in aqueous solutions.

Main Results:

• Successful synthesis of Cs[H2NB2(C6F5)6] with a monatomic, solute-free cesium cation.
• Discovery of a novel C2 symmetrical conformation for the [H2NB2(C6F5)6](-) anion.
• Observation of an unprecedented 16-coordinate Cs(+) cation with a tetracosahedral arrangement of fluorine atoms.
• Demonstration of poor solubility of the cesium compound in water, enabling efficient Cs(+) separation.

Conclusions:

• The unique coordination environment of Cs[H2NB2(C6F5)6] presents novel structural features.
• The compound's properties suggest significant potential for applications in nuclear waste remediation, as a cesium poisoning antidote, and in cesium-based radiotherapy.