Communication: Revised electron affinity of SF6 from kinetic data.

Area of Science:

• Physical Chemistry
• Chemical Physics
• Atomic and Molecular Physics

Background:

• Experimental data on electron attachment to SF6 and detachment from SF6- were previously established.
• Accurate modeling of these processes requires precise knowledge of molecular properties.

Purpose of the Study:

• To reevaluate existing experimental data for thermal electron attachment to SF6 and thermal detachment from SF6-.
• To refine the adiabatic electron affinity (EA) of SF6 and the bond dissociation energy of SF6-.
• To assess the impact of new computational data on electron detachment rate constants.

Main Methods:

• Third-law analysis of experimental data for electron attachment/detachment.
• Incorporation of high-precision calculations for SF6- harmonic frequencies and anharmonicities.
• Modeling of vibrational partition functions.

Main Results:

• The adiabatic electron affinity (EA) of SF6 was revised downwards from 1.20 eV to 1.03 eV (±0.05 eV).
• The bond dissociation energy E(0,dis) for SF6- → SF5- + F was reduced to 1.44 eV (±0.05 eV).
• Significant changes in modeled vibrational partition functions were observed.

Conclusions:

• The revised EA and bond dissociation energy necessitate adjustments in models of electron detachment from SF6-.
• The updated parameters provide a more accurate basis for understanding electron-SF6 interactions.