About Face

See allHide authors and affiliations

Science  23 Jun 2000:
Vol. 288, Issue 5474, pp. 2097
DOI: 10.1126/science.288.5474.2097d

The spacing between chains in conjugated polymers affects their photoluminescent (PL) properties. If the functional groups containing the conjugated double bonds are too close, fluorescence tends to be quenched; this effect can limit the performance of these materials in thin films. McQuade et al. systematically varied interchain distances in poly(p-phenylene ethynylenes) in Langmuir films in which the conjugated groups of the polymer chain are oriented edge-on at the air-water interface and thus pack face-to-face. By changing the side chains from methyl to isopropyl groups, they increased the interchain spacing by 20%—but more than doubled the efficiency (the PL quantum yield) from 7% to 16%.—PDS

J. Am. Chem. Soc., in press.

Navigate This Article