Photodissociation dynamics of SO₂ via the $G̃$¹B₁ state: The O(¹D₂) and O(¹S₀) product channels

Produced by both nature and human activities, sulfur dioxide (SO₂) is an important species in the earth’s atmosphere. SO₂ has also been found in the atmospheres of other planets and satellites in the solar system. The photoabsorption cross sections and photodissociation of SO₂ have been studied for several decades. In this paper, we reported the experimental results for photodissociation dynamics of SO₂ via the $G̃$¹B₁ state. By analyzing the images from the time-sliced velocity map ion imaging method, the vibrational state population distributions and anisotropy parameters were obtained for the O(¹D₂) + SO(X³Σ⁻, a¹Δ, b¹Σ⁺) and O(¹S₀) + SO(X³Σ⁻) channels, and the branching ratios for the channels O(¹D₂) + SO(X³Σ⁻), O(¹D₂) + SO(a¹Δ), and O(¹D₂) + SO(b¹Σ⁺) were determined to be ∼0.3, ∼0.6, and ∼0.1, respectively. The SO products were dominant in electronically and rovibrationally excited states, which may have yet unrecognized roles in the upper planetary atmosphere.