Electron Impact Studies of Sulfur Dioxide and Sulfuryl Fluoride

Abstract

Mass spectra and appearance potentials have been obtained for the principle positive and negative ions of SO₂ and SO₂F₂. Ionic heats of formation and probable ionization‐dissociation procesess are tabulated. The electron‐impact data for SO₂ support the values of 3.3 ev for D(S₂) and 5.15 ev for D(SO). The molecular ionization potential is in good agreement with recent photoionization measurements. The ΔH_f(SO₂F₂) = — 205 kcal/M is calculated from the appearance potential of the SO₂⁺ ion. Other ionic heats of formation are based on this value. The ΔH_f(SO⁺) is in good agreement for both molecules. A minimum value of 3.0 ev is calculated for the electron affinity of F₂ from the appearance potential of the F₂^‐ ion.