First coal solvation involves formation of {HEAD ~ free radicals} which are stabilized by {TAIL ~ hydrogen} 
are stabilized by
First coal solvation involves formation of { HEAD ~ free radicals } which are stabilized by { TAIL ~ hydrogen }
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL REL TAIL TAIL TAIL TAIL TAIL