Structures and electron affinities of BrO₂F₂ and BrO₂F₃

Abstract

Five hybrid Hartree–Fock/density functional theory (DFT) and pure DFT methods with DZP++ basis sets were used for predictions of the structures and energetics of molecules and anions, and the neutral-anion energy separations in the series (n = 2 and 3). The results show that the anions have conventional structures and the neutrals are unconventional with big electron affinities. For neutral BrO₂F₂, a chain complex F–Br ··· O–O–F lies lowest with adiabatic electron affinity (EA_ad) value of 4.57 eV (BP86/DZP++), while the conventional [F–(:BrO₂)–F]^– (C_{2 v}) quasi-trigonal bipyramid lies lowest for the negative ion. For neutral BrO₂F₃, a unusual complex O–Br(F₂) ··· O–F lies lowest with EA_ad of 4.48 eV, while the conventional complex [F ··· Br(F₂)O₂]⁻ (C_s) lies lowest for anion. For n = 2 and 3, reactions energies of some dissociation paths for O₂ and OF eliminations exhibit the favorable endothermicities, respectively, the anions have much larger values.

Keywords:

• density functional theory
• electron affinity
• BrO₂F₃/BrO₂ F₃ ^-
• molecular structure

Acknowledgements

This work was supported by the China, Sustentation Fund of Scientific and Technological Development Project of Beijing Municipal Education Commission (No. KM200810017007) and Reserch Fund (No. N07-05) of Beijing Institute of Petro-Chemical Technology, Beijing 102617, P. R. China. We thank the editors and reviewers for their time, patience and help. We are grateful to Professor Henry F. Schaefer III of University of Georgia, who supplied us the DZP++ basis sets.