Homonuclear molecules may consist of various numbers of atoms.
Homonuclear diatomic molecules include hydrogen (H2), oxygen (O2), nitrogen (N2) and all of the halogens.
Homonuclear tetratomic molecules include arsenic (As4) and phosphorus (P4).
Sulfur forms several allotropes containing different numbers of sulfur atoms, including diatomic, triatomic, hexatomic and octatomic (S2, S3, S6, S8) forms, though the first three are rare.
The element carbon is known to have a number of homonuclear molecules, including diamond and graphite.