thiosulfide

A thiosulfide is a chemical compound containing a sulfur-sulfur bond where one sulfur atom is bonded to two other atoms, and the other sulfur atom is bonded to one atom. More specifically, it refers to an anion with the formula S₂²⁻. This dianion is characterized by a formal single bond between the two sulfur atoms. Thiosulfides are found as structural units within certain chemical compounds, often as salts with alkali metals or other cations. For instance, sodium thiosulfide, Na₂S₂, is a known compound. The thiosulfide ion is isoelectronic with the peroxide ion (O₂²⁻) and shares some similarities in its bonding. The sulfur-sulfur bond length in the thiosulfide ion is typically around 2.1 Ångstroms. These compounds can be formed through reactions involving elemental sulfur and metal sulfides under reducing conditions. While not as common as simple sulfides (S²⁻) or polysulfides (Sₙ²⁻ where n > 2), thiosulfides represent a specific and interesting bonding arrangement within sulfur chemistry.