Ab initio and DFT study of the geometric structures and static dipole (hyper)polarizabilities of aromatic anions.

The geometries and the static dipole (hyper)polarizabilities (alpha, beta, gamma) of a series of aromatic anions were investigated at the ab initio (HF, MP2, and MP4) and density functional theory DFT (B3LYP) levels of theory. The anions chosen for the present study are the benzenethiolate (Ph-S-), benzenecarboxylate (Ph-CO2-), benzenesulfinate (Ph-SO2-), benzenesulfonate (Ph-SO3-), and 1,3-benzenedicarboxylate (1,3-Ph-(CO2)2(2-)). For benzenethiolate anion, additional alpha, beta, and gamma calculations were performed at the coupled cluster CCSD level with MP2 optimized geometries.

3,4-Vinylenedioxythiophene (VDOT): a new building block for thiophene-based pi-conjugated systems.

The synthesis of the title compound and its use as a building block in pi-conjugated systems are presented.

Novel D-pi-A chromophores based on the fulvene accepting moiety.

[reaction: see text] Novel D-pi-A chromophores based on the fulvene accepting moiety and p-dimethylamino phenyl and 1,3-dithiole-2-ylidene donor moieties have been prepared. The X-ray structures of two representative derivatives have been determined. Examination of the UV-visible spectra and cyclic voltamperometry data revealed remarkable sensitivity of the electronic structure of these derivatives to substituents at the cyclopentadiene ring.