Some alternative names for this compound are sulfur monochloride (the name implied by its empirical formula, SCl), disulphur dichloride (British English Spelling) and sulphur monochloride (British English Spelling). S₂Cl₂ has the structure implied by the formula Cl-S-S-Cl, wherein the angle between the Cl^a-S-S and S-S-Cl^b planes is 90°. This structure is referred to as gauche, and is akin to that for H₂O₂. A different isomer of S₂Cl₂ is S=SCl₂; this isomer forms transiently when S₂Cl₂ is exposed to UV-radiation (see thiosulfoxides).

This substance is listed in Schedule 3 Part B - Precursor Chemicals of the Chemical Weapons Convention (CWC). Facilities that produce and/or process and/or consume Scheduled chemicals may be subject to control, reporting mechanisms and inspection by the OPCW (Organisation for the Prohibition of Chemical Weapons).

Pure disulfur dichloride is a yellow liquid that smokes in air due to reaction with water:

It is synthesized by partial chlorination of elemental sulfur. The reaction takes place at usable rates at room temperature. In the laboratory, chlorine gas is led into a flask containing elemental sulfur. As disulfur dichloride is formed, the contents become a golden yellow liquid:

Excess chlorine gives sulfur dichloride which causes the liquid to become less yellow and more orange-red:

The reaction is reversible, and upon standing, SCl₂ releases chlorine to revert to the disulfur dichloride. Disulfur dichloride has the ability to dissolve large quantities of sulfur, which reflects in part the formation of polysulfanes:

Pure disulfur dichloride is obtained by distilling the yellow-orange liquid over excess elemental sulfur.

S₂Cl₂ also arises from the chlorination of CS₂ as in the synthesis of thiophosgene.

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