Semiconducting Organic Assemblies Prepared from Tetraphenylethylene Tetracarboxylic Acid and Bis(pyridine)s via Charge-Assisted Hydrogen Bonding.

Principles of crystal engineering have been applied toward the construction of supramol. assemblies between an acid-functionalized tetraphenylethylene deriv. and three different bis(pyridine)s [4,4'-bis(pyridyl)ethylene, 4,4'-bis(pyridyl)ethane, and 4,4'-bipyridine]. Each assembly was structurally characterized, and charge transfer interactions within each sample were visually apparent. Quantum chem. calcns. were used to det. crystal band structure and band gap magnitude, and elec. properties of the materials were measured using conducting probe at. force microscopy (CP-AFM). The crystals displayed charge-carrier capability, and the magnitude of semicond. varied systematically as a function of conjugation in the bis(pyridine) component. Crystals incorporating 4,4'-bis(pyridyl)ethylene and 4,4'-bipyridine displayed conductivities comparable to those of established org. semiconductors (μeff = 0.38 and 1.7 × 10-2 cm2/V·s, resp.). [on SciFinder(R)]