A R T I C L E S
Cardolaccia et al.
diffusion,45-47 and excited-state energy transfer within ag-
gregates consisting of π-conjugated molecular units11,18,48 have
been studied by using solution-based techniques.
Chart 1
While considerable work has been carried out on supramo-
lecular structures comprised of organic π-conjugated systems,
relatively few studies have explored the properties of aggregates
or gels consisting of metal-organic or organometallic π-conju-
gated oligomers or polymers.49-53 These systems are of interest,
as introduction of metal centers into optical or electronic
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Inspired in part by the reports of the self-assembly properties
of suitably substituted π-conjugated oligomers reported by
Meijer, Stupp, Ajaygosh, and others,3,4,8,10,15,20 we designed the
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hydrocarbon solvents. The PAOs feature a π-conjugated plati-
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