{HEAD ~ The photographic element} 2 wherein {TAIL ~ T1} is a timing or linking group which functions by electron transfer down an unconjugated chain and is of the formula 
wherein
{ HEAD ~ The photographic element } 2 wherein { TAIL ~ T1 } is a timing or linking group which functions by electron transfer down an unconjugated chain and is of the formula
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH