Sulfur difluoride explained

Sulfur difluoride is an inorganic compound with the chemical formula SF₂. It can be generated by the reaction of sulfur dichloride and potassium fluoride or mercury(II) fluoride at low pressures:

SCl₂ + 2 KF → SF₂ + 2 KCl

SCl₂ + HgF₂ → SF₂ + HgCl₂

The F−S−F bond angle is 98°, and the length of S−F bond is 159 pm.^[1] The compound is highly unstable, dimerising to FSSF₃. This unsymmetrical isomer of S₂F₄ is proposed to arise via insertion of SF₂ into the S−F bond of a second molecule SF₂:

It can also be formed from oxygen difluoride and hydrogen sulfide:

OF₂ + H₂S → SF₂ + H₂O

Notes and References

1. 10.1126/science.164.3882.950. Microwave Spectrum and Structure of Sulfur Difluoride. 1969. Johnson. D. R.. Powell. F. X.. Science. 164. 3882. 950–1. 17775599. 1969Sci...164..950J . 46046291 .