Protonation of N₂O and NO₂ in a solid phase

Area of Science:

• Solid-state chemistry
• Acid-base catalysis
• Supramolecular chemistry

Background:

• The study investigates the interaction of strong solid acids with gaseous molecules.
• Understanding the behavior of superacids is crucial for catalysis and materials science.

Purpose of the Study:

• To elucidate the mechanism of N2O adsorption and protonation on a potent solid acid.
• To characterize the resulting cationic species and their acid properties.

Main Methods:

• Adsorption of gaseous N2O on H(CHB11F11) solid acid.
• Spectroscopic analysis to identify and characterize the protonated species.
• Theoretical calculations to understand charge distribution and bonding.

Main Results:

• Formation of the N≡N-OH+ cation through protonation of N2O by H(CHB11F11).
• The cation exists as an asymmetric proton disolvate (L1-H+-L2), with N2O and CHB11F11- as ligands.
• Protonation of NO2 leads to a reactive cation radical NO2H˙+, which further reacts with NO2.
• Two types of N2OH+ cations are identified: a Brønsted superacid and a Lewis acid.

Conclusions:

• H(CHB11F11) acts as a strong Brønsted acid, facilitating N2O protonation.
• The resulting N2OH+ cation displays a unique duality of Brønsted and Lewis acidity.
• This study provides insights into the fundamental interactions between superacids and small molecules.