We describe a series of nine new complex salts in which electron-rich Ru(II) or Fe(II) centers are connected via pi-conjugated bridges to six electron-accepting N-methyl-/N-arylpyridinium groups. This work builds upon our previous preliminary studies (Coe , B. J. J. Am. Chem. Soc. 2005, 127, 13399-13410; J. Phys. Chem. A 2007, 111, 472-478), with the aims of achieving greatly enhanced NLO prope...

We present the structure-dependent nonlinear optical (NLO) properties of fully conjugated tri(perylene bisimides) (triPBIs) toward the understanding of the role of conformational flexibility and pi-electron conjugation in molecular NLO properties of model graphene-nanoribbon (GNR)-like molecules. In the present paper, we report the NLO absorption properties of the triPBIs in toluene excited at ...

Helicene molecules have enormous potential utility. Helicenes are foreseen to act as organic semiconductors, components of fast optical switches, asymmetric catalysts, and molecular actuators. Acene molecules have potential utility as organic semiconductors due to their linear, conjugated pi-electron system. Yet despite this multitude of uses, there has been no method of preparing polymeric hel...

pi-Conjugated polymers that are electrochemically cycled in ionic liquids have enhanced lifetimes without failure (up to 1 million cycles) and fast cycle switching speeds (100 ms). We report results for electrochemical mechanical actuators, electrochromic windows, and numeric displays made from three types of pi-conjugated polymers: polyaniline, polypyrrole, and polythiophene. Experiments were ...

The non-aggregating nature of a water-soluble pi-conjugated polythiophene has been characterised by concentration independent thermal denaturing.

Cross-conjugated enediynes cannot follow the Bergman cycloaromatization as it involves a methylenediyne moiety with only five pi e(-), insufficient for aromatization. Under reductive conditions the cyclization is made feasible by generating a product with a Hückel number of pi electrons. We illustrate this principle and demonstrate for the first time an anionic cyclization of a cross-conjugated...

We predict properties of triplet excited states in single-walled carbon nanotubes (CNTs) using a time-dependent density-functional theory (TD-DFT). We show that the lowest triplet state energy in CNTs to be about 0.2-0.3 eV lower than the lowest singlet state energies. Like in pi-conjugated polymers, the lowest CNT triplets are spatially localized. These states show strong optical absorption at...

We study coherent phonon transport through organic, π-conjugated molecules. Using first principles calculations and Green's function methods, we find that the phonon transmission function in cross-conjugated molecules, like meta-connected benzene, exhibits destructive quantum interference features very analogous to those observed theoretically and experimentally for electron transport in simila...