Potassium nitride

Potassium nitride is an unstable chemical compound. Several syntheses were erroneously claimed in the 19th century, and by 1894 it was assumed that it did not exist.

However, a synthesis of this compound was claimed in 2004. It is observed to have the anti-Titanium(III) iodide structure below 233 K, although a -type structure should be more stable. Above this temperature, it converts to an orthorhombic phase. This compound was produced by the reaction of potassium metal and liquid nitrogen at 77 K under vacuum:
 * 6K + N2 → 2K3N

This compound decomposes back into potassium and nitrogen at room temperature.

This compound is unstable due to steric hindrance.