Octaoxygen

Octaoxygen, also known as ε-oxygen or red oxygen, is an allotrope of oxygen consisting of eight oxygen atoms. This allotrope forms at high pressure and remains stable across a wide pressure range at room temperature (between 10 and 96 GPa). If it is further compressed past 96 GPa, then it transitions into a metallic, superconducting state.

The material is dark red and unlike other forms allotropes of oxygen is has no magnetic character, due to its unpaired electrons being forced to overlap.