Modeling energy transport in $\pi $-conjugated dendrimers containing triple bonds

An accurate, transferrable, and computational efficient adapted Su-Schrieffer-Heeger model Hamiltonian is developed to describe triple bonds in linear and fractal-dimensional $\pi $-conjugated systems. Chemical accuracy in the computed optical gaps is found for the cases of poly-(thiophene-ethynylene) and ploy-phenylacetylene of arbitrary lengths, with all errors less than 3{\%} as compared to existing UV-visible adsorption spectra. The computed exciton migration processes in the phenylacetylene dendrimers indicates that such conjugated Bethe tree structures are efficient energy transduction funnels.