For example, a first one of the conducting layers may be comprised of {TAIL ~ a first material} and {HEAD ~ a second material} 
For example , a first one of the conducting layers may be comprised of { TAIL ~ a first material } and { HEAD ~ a second material }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD