{TAIL ~ These compounds} may be in a crystalline state having metallic cations of {HEAD ~ two different valences}, or electronic states, in the inorganic crystal 
{ TAIL ~ These compounds } may be in a crystalline state having metallic cations of { HEAD ~ two different valences } , or electronic states , in the inorganic crystal
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH