MnCl3

MnCl3, or manganese(III) chloride, is a chemical species in which manganese is in the +3 oxidation state coordinated to three chloride ligands. In practice, the anhydrous salt is not typically isolated as a simple molecular compound; MnCl3 is more commonly encountered as polymeric or coordination adducts and as a component of complex salts. The compound is highly moisture sensitive and readily hydrolyzes in air or water, often forming basic manganese oxychloride species and releasing hydrochloric acid.

In the solid state, Mn3+ centers are typically six-coordinate in octahedral environments, with chloride ligands that can bridge between manganese centers to generate extended networks. In solution, MnCl3 species tend to form various chloro-complexes and generally behave as oxidizing agents because Mn3+ can be reduced to Mn2+.

Preparation and occurrence are primarily in the context of inorganic synthesis and coordination chemistry. MnCl3 is usually generated under strictly anhydrous conditions or studied as part of coordination complexes with donor ligands such as acetonitrile, pyridine, or other chloride-containing adducts. It is rarely used as a standalone reagent, being more important as a precursor to manganese(III) complexes and related compounds in research settings.

Safety and handling follow the general cautions for manganese compounds and for moisture- and air-sensitive chlorides. MnCl3 compounds are typically strong oxidizers and can be corrosive; appropriate precautions include inert-atmosphere techniques and avoidance of moisture contact.