Four polymers that contain alkyl chains branched at different positions on the polymer backbone are prepared. A polymer with 4-decyltetradecyl chains gives an impressive mobility of 3.62 cm(2) V(-1) s(-1) . This may arise from tighter polymer packing as well as stacking conformation change of the polymer backbone induced by the branching of the alkyl chains.

The two-dimensionally connected metal-organic frameworks (MOFs) Ni(HIB) and Cu(HIB) (HIB = hexaiminobenzene) are bulk electrical conductors and exhibit ultraviolet-photoelectron spectroscopy (UPS) signatures expected of metallic solids. Electronic band structure calculations confirm that in both materials the Fermi energy lies in a partially filled delocalized band. Together with additional structural characterization and microscopy data, these results represent the first report of metallic behavior and permanent porosity coexisting within a metal-organic framework.

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Ambipolar transport behavior in isoindigo-based conjugated polymers is observed for the first time. Fluorination on the isoindigo unit effectively lowers the LUMO level of the polymer and significantly increases the electron mobility from 10(-2) to 0.43 cm(2) V(-1) s(-1) while maintaining high hole mobility up to 1.85 cm(2) V(-1) s(-1) for FET devices fabricated in ambient. Further investigation indicates that fluorination also affects the interchain interactions of polymer backbones, thus leading to different polymer packing in thin films.