wherein {HEAD ~ the aromatic compound} is an organic pigment, {TAIL ~ an organic light emitter}, or an organic semiconductor 
is
wherein { HEAD ~ the aromatic compound } is an organic pigment , { TAIL ~ an organic light emitter } , or an organic semiconductor
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH