Mononitrogen monosulfide is an inorganic compound

Inorganic compound

Inorganic compounds have traditionally been considered to be of inanimate, non-biological origin. In contrast, organic compounds have an explicit biological origin. However, over the past century, the classification of inorganic vs organic compounds has become less important to scientists,...

 with the formula

Chemical formula

A chemical formula or molecular formula is a way of expressing information about the atoms that constitute a particular chemical compound....

 SN. It is the sulfur analogue of nitric oxide

Nitric oxide

Nitric oxide, also known as nitrogen monoxide, is a diatomic molecule with chemical formula NO. It is a free radical and is an important intermediate in the chemical industry...

, NO. It can be produced through electrical discharges in mixtures of nitrogen and sulfur compounds, as well as the reaction of nitrogen with sulfur vapor. The valence electrons of this compound matches those of nitrogen oxide

Nitrogen oxide

Nitrogen oxide can refer to a binary compound of oxygen and nitrogen, or a mixture of such compounds:* Nitric oxide, also known as nitrogen monoxide, , nitrogen oxide* Nitrogen dioxide , nitrogen oxide...

. In outer space

Outer space

Outer space is the void that exists between celestial bodies, including the Earth. It is not completely empty, but consists of a hard vacuum containing a low density of particles: predominantly a plasma of hydrogen and helium, as well as electromagnetic radiation, magnetic fields, and neutrinos....

, this compound was first detected in the giant molecular cloud Sgr B2. It was subsequently observed in cold dark clouds and in the coma of comets.

Mononitrogen monosulfide exists as a resonance structure of which a species with a bond order of one accompanied by charge separation, is the major contributor.