TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Composition: The halogen is bromine or chlorine. An oxidant used in cyclization reaction is oxygen or iodine.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: The solvent additive is chosen from 1,6-dichlorohexane, 1,6-dibromohexane, 1,6-diiodohexane, diiodooctane, 1,8-dithioloctane, 1,8-dichlorooctane, 1,8-dibromooctane, 1,8-diiodooctane, decanedinitrile, 1,10-dithioldecane, 1,8-dichlorodecane, 1,8-dibromodecane, 1,8-diiododecane, chloronaphthalene, octanedithiol, 1,6-dithiolhexane, octadinitrile, dodecanedinitrile and 1- chloronaphthalene.    TECHNOLOGY FOCUS - POLYMERS - Preparation (claimed): The oligomer compound (I) is prepared by coupling two or more perylenediimide monomers with ethylene bridge, or coupling halogen substituted monomer or oligomer to trans-1,2-bis(tributylstannyl)ethane, and then cyclizing. Preferred Composition: The compound (I) is preferably of formulae (Ia)-(Ic). The lowest unoccupied molecular orbital level of the compound (I) is -4 eV. The oligomer compound (I) forms a helical, waggling or mixed helical and waggling superstructure. The electron donor is chosen from group 1A metal, group 1A metal arene, poly(3-hexylthiophene-2,5-diyl), poly(2-methoxy-5-(3,7-dimethyloctyloxy)-l,4-phenylenevinylene), poly(2-methoxy-5-(2'-ethyl-hexyloxy)-l,4-phenylenevinylene), N,N-diisopropyl-3-pentylamine, N-ethyldiisopropylamine, and 1,2,2,6,6-pentamethylpiperidine, thieno(3,4-b)thiophene/benzodithiophene, poly(4,4-dioctyldithieno(3,2-b:2',3'-d)silole-2,6-diyl-alt-(2,1,3-benzothiadiazole)-4,7-diyl), and poly((4,8-bis(5-(2-ethylhexyl)thiophene-2-yl)benzo(l,2-b:4,5-b')dithiophene)-2,6-diyl-alt-(4-(2-ethylhexanoyl)-thieno(3,4-b)thiophene)-2,6-diyl). EXAMPLE - In standard photocyclization glassware, 1 g uncyclized dimer of formula (i) was dissolved in 450 mL benzene, 100 mg iodine was added, and resultant purple solution was photoirradiated using 450 W mercury lamp for 36 hours with slow bubbling of air through the solution. The resultant pink reaction mixture was extracted with 400 mL saturated sodium bicarbonate and 400 mL brine, concentrated under reduced pressure, the residue was treated with 50 mL methanol, and resultant red solid was purified by column chromatography, obtain 0.84 g oligomer compound (Ia) with yield of 83%.