{HEAD ~ Each molecular moiety} may be different from {TAIL ~ every other molecular moiety} within the array, such that the array is a “combinatorial” library of the different molecular moieties 
different from
{ HEAD ~ Each molecular moiety } may be different from { TAIL ~ every other molecular moiety } within the array , such that the array is a “ combinatorial ” library of the different molecular moieties
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH