dianthracene dianthrene 5,6,11,12-Tetrahydro-5,12:6,11-di[1,2]benzenodibenzo[a,e]cyclooctene 9,10-(9,10-Dihydro-9,10-anthracenediyl)-9,10-dihydroanthracene Paraanthracene Paraanthrene 5,12[1',2']:6,11[1'',2'']-Dibenzenodibenzo[a,e]cyclooctene, 5,6,11,12-tetrahydro- Anthracene photodimer