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Sulfur dioxide and hypohalous acids (HOX, X=F, Cl, Br, I) are ubiquitous molecules in the atmosphere that are central to important processes like seasonal ozone depletion, acid rain, and cloud nucleation. We present the first theoretical examination of the HOX⋯SO₂binary complexes and the associated trends due to halogen substitution. Reliable geometries were optimized at the CCSD(T)/aug‐cc‐pV(T+d)Z level of theory for HOF and HOCl complexes. The HOBr and HOI complexes were optimized at the CCSD(T)/aug‐cc‐pV(D+d)Z level of theory with the exception of the Br and I atoms which were modeled with an aug‐cc‐pwCVDZ‐PP pseudopotential. 27 HOX⋯SO₂complexes were characterized and the focal point method was employed to produce CCSDT(Q)/CBS interaction energies. Natural Bond Orbital analysis and Symmetry Adapted Perturbation Theory were used to classify the nature of each principle interaction. The interaction energies of all HOX⋯SO₂complexes in this study ranged from 1.35 to 3.81 kcal mol⁻¹. The single‐interaction hydrogen bonded complexes spanned a range of 2.62 to 3.07 kcal mol⁻¹, while the single‐interaction halogen bonded complexes were far more sensitive to halogen substitution ranging from 1.35 to 3.06 kcal mol⁻¹, indicating that the two types of interactions are extremely competitive for heavier halogens. Our results provide insight into the interactions between HOX and SO₂which may guide further research of related systems.

Reaction of carbene‐stabilized disilicon (1) with the lithium‐based dithiolene radical (2^.) affords the first dianionic silicon tris(dithiolene) complex (3). Notably, the formation of3represents the unprecedented utilization of carbene‐stabilized disilicon (1) as a silicon‐transfer agent. The nature of3was probed by multinuclear NMR spectroscopy, single‐crystal X‐ray diffraction, and DFT computations.

Whereas low‐temperature (−78 °C) reaction of the lithium dithiolene radical1^.with boron bromide gives the dibromoboron dithiolene radical2^., the parallel reaction of1^.with (C₆H₁₁)₂BCl (0 °C) affords the dicyclohexylboron dithiolene radical3^.. Radicals2^.and3^.were characterized by single‐crystal X‐ray diffraction, UV/Vis, and EPR spectroscopy. The nature of these radicals was also probed computationally. Under mild conditions,3^.undergoes unexpected thiourea‐mediated B−C bond activation to give zwitterion4, which may be regarded as an anionic dithiolene‐modified carbene complex of the sulfenyl cation RS⁺(R=cyclohexyl).