Bonding and electronic structure of XeF3-

Area of Science:

• Inorganic Chemistry
• Computational Chemistry
• Chemical Physics

Background:

• The structure and bonding of polyatomic anions like XeF3- are not fully understood.
• Existing models struggle to accurately predict the stability and dissociation energies of such species.

Purpose of the Study:

• To experimentally measure the xenon-fluoride bond dissociation energy in XeF3-.
• To elucidate the bonding characteristics and low-energy structures of XeF3- using theoretical approaches.

Main Methods:

• Energy-resolved collision-induced dissociation (CID) experiments were performed on XeF3-.
• Molecular orbital (MO) calculations, including diradical and orbital interaction models, were employed.
• Electronic structure calculations identified potential low-energy geometries.

Main Results:

• The measured Xe-F bond dissociation energy in XeF3- is 0.84 ± 0.06 eV.
• This experimental value exceeds predictions from electrostatic and three-center, four-electron bonding models.
• Two low-energy singlet structures (Y- and T-shaped) and a higher-energy triplet state were identified for XeF3-.
• Calculations favor the Y-shaped geometry as the most stable, with pseudorotation possible through the T-shaped structure.

Conclusions:

• The bonding in XeF3- is more complex than suggested by simpler models.
• Dissociation likely proceeds via rearrangement to the T-shaped structure before fluoride loss.
• Experimental and computational methods provide complementary insights into the stability and reactivity of XeF3-.