MnO6

MnO6 is not a simple, stable molecular species known in isolation. In inorganic chemistry, the term most often refers to the octahedral MnO6 unit that appears as part of larger oxide solids and coordination compounds. Six oxide ligands coordinate to a central manganese atom in approximately octahedral geometry, with the oxidation state of manganese depending on the overall compound. Common valences include Mn3+ in perovskite-like materials such as LaMnO3 and Mn4+ in various manganese oxides.

In solid-state oxides, MnO6 octahedra link by sharing corners or edges to form crystalline networks. For example, in rutile-type MnO2, MnO6 octahedra share edges to create one-dimensional chains, while in perovskites such as LaMnO3, the octahedra corner-share to build a three-dimensional lattice. Distortions from an ideal octahedral geometry are common, particularly for Mn3+ due to the Jahn-Teller effect, which can elongate Mn–O bonds along a specific axis.

MnO6 units also occur in coordination chemistry as building blocks within manganese-oxide clusters and in complex oxoanions in solution, though there is no widely recognized, stable neutral MnO6 molecule under ordinary conditions. Consequently, MnO6 is best understood as a structural motif that appears in various manganese oxide frameworks rather than as an isolated compound.

See also: manganates and permanganates, manganese oxide minerals, perovskites, Jahn-Teller effect.