Abstract: Anthracenophanes and 1, 2-dianthrylethanes were studied as models of excimers. It was found that (1) there are natively various structures of excimer,(2) the so-called “n= 3 rule” is not valid in the case of dianthrylalkanes,(3) the excimers of 1, 2-dianthrylethanes show two different kinds of structures, and (4) excimer fluorescence lifetimes are reduced due to the photodimerization in the case of syn-[2.2](1, 4) anthracenophane,[2.2](1, 4)(9, ...