does S2 Exists? if not what ius reason for this ? as , O2 exists .

@ pranav 
S2 is an allotropes of sulpher in the form of disulpher , but disulpher is in gaseous state and have very less energy , as compared to s8 , which is a solid substances and having high energy . 
and s2 exist only in vapour state , 
due to that sulpher exist in s8 state and not in s2 state . 

HOPE IT CLEARS ..