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Wittig-Horner reaction was employed in the synthesis of a number of pi-extended tetrathiafulvalene (TTF) derivatives using phosphonate esters and various acequinones as precursor compounds. TTF derivatives exhibit good donor properties based on electrochemical analyses. Theoretical investigations have been conducted to establish the molecular geometries of these compounds. Molecular structure optimization was used to investigate the mechanism of oxidation in the various TTF derivatives.

Experimental techniques and quantum-chemical calculations were used to prepare and characterize the structural and electronic properties of spiroannelated methanofullerenes having quinone-type addends, such as TCNQ and DCNQI analogues. The noval methanofullerenes showed irreversible cyclic voltammograms with further reduction peaks, and the conjugated cyclohexadienone derivatives showed better acceptor abilities than the parent Csub60.

The torsional potential of biisothianaphthene was examined and compared with that of bithiophene. The computations were conducted at the ab initio and semiempirical Hartree-Fock, ab initio post-Hartree-Fock and density functional theory (DFT) levels. DFT computations were found to yield geometries very close to those obtained at the MP2 level but fail in describing the energetics of the torsional potentials because they overstabilize planar conformers.

A new type of sulfur-containing donor-acceptor compounds, N,N'-dicyanobenzo(b)naphtho(2,3-e)(1,4)dithiin-6,11-quinonediimine (9a) and N,N'-dicyanobenzo(b)naphtho(2,3-e)(1,4)oxathiin-6,11-quinonediimine (10a), derived from N,N'-dicyano-p-quinonediimine (DCNQI) are synthesized, characterized, and subjected to a theoretical study. Syn/anti isomerization occurs in solution, with the favored N-CN substituents configurations of a syn isomer for 9 and an anti isomer for 10. The donor-acceptor ability of the compounds is further reinforced by cyclic voltammetry calculations.

The electron acceptor 11,11,12,12-tetracyano-1,4-anthroquinodimethanes (1,4-TCAQs) show the property of photoinduced charge-transfer, which is shown by the band in the blue part of the visible region in the UV spectra. The band shifts bathochromically when the naphthalene bears electron-releasing methoxy substitutes, showing an intramolecular charge transfer from the donor naphthalene moeity to the acceptor tetracyano-o-quinodimethane ring of the molecule. The TCAQs is prepared from substituted 1,4-anthracenediones with malononitrile in the presence of Lehnert's reagent.

A study was done on the photoelectron valence band spectra of metal-free phthalocyanine thin films using the valence effective Hamiltonian nonempirical technique. It was shown that electronic states in beta-H2Pc are localized within single phthalocyanine molecules. Analysis of the electronic structure of beta-H2Pc shows that the electronic characteristics of the benzene moieties are preserved in the phthalocyanine macrocycle which results from the joining of four benzene rings to the central carbon-nitrogen methineimine-like ring.

An exTTF-based macrocyclic receptor is described that has associated [C.sub.60] with a binding constant in chlorobenzene at room temperature. The studies have shown an improvement of 3 orders of magnitude with respect to the previous examples of exTTF-based receptors and one of the highest binding constants toward [C.sub.60].

The presence of interligand [pi]-[pi] stacking in a single ionic iridium complex has increased its stability when used in a double-layer solid-state light-emitting electrochemical cell (LEC). Density functional theory calculations have shown that this stacking is maintained in the excited-state that has protected the complex against ligand-exchange reactions.