Poly , long lived absorption

Photoinduced absorption studies of the oligomer have shown that the dominant long-lived photocarriers are bipolarons formed by interchain charge separation. The lifetimes of the bipolarons in poly(l-(A-carbazo-lyl)penta-5-acetoxy-l,3-diyn) are of the order of seconds at 80 K. The polymer of 1-(A-carbazolyl)-penta-l,3-diyne-5-ol, which is an intermediate compound in the synthesis of (61), has a very low band gap energy (1.6 eV) exhibits a strong non-linear optical... 

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