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Conductive boron-doped diamond supports were used for achieving the generalization of some of the interpretations of heterogeneous catalysis in relation to the oxide film electrocatalysts and studying the catalytic properties of noble-metal oxide modifications from the level of submonolayer to a few monolayers. The results indicate the presence of distinct oxidation state changes because the cyclic voltammograms at RuO2 and IrO2 thick-film electrodes show poorly resolved peaks that convolute into broad flat maxima.

A study is conducted to determine the gas-phase ionization and attachment energy (IE and AE) values of some p- and o-cyano derivatives of anisole and thioanisole. The data indicate that poly (p-phenylene sulfide) is more suitable than poly (p-phenylene oxide) to carry electricity under mild doping.

Gas-phase ionization and attachment energy (IE and AE) values of the first oligomers of 2-thienyl ketone have been determined experimentally. The results of theoretical HF/6-31G** calculations agree with the assignments of the ultraviolet photoelectron spectra. Extrapolation to the corresponding polymer was allowed by the constant value of the HOMO energy. The LUMO energy for the oligomers and for an ideal gas-phase poly(thienylene ketone) was obtained by a combined analysis of the AE values, the electrochemical reduction data and the results of ab initio 6-31G**.

The analysis of the IR carbonyl bands of some 3-(4'-substituted phenylsulfanyl)-1-methyl-2-piperidones 1-6 bearing substituents: NO₂ (compound 1), Br (compound 2), Cl (compound 3), H (compound 4) Me (compound 5) and OMe (compound 6) supported by B3LYP/6-31+G(d,p) and PCM calculations along with NBO analysis (for compound 4) and X-ray diffraction (for 2) indicated the existence of two stable conformations, i.e., axial (ax) and equatorial (eq), the former corresponding to the most stable and the least polar one in the gas phase calculations. The sum of the energy contributions of the orbital interactions (NBO analysis) and the electrostatic interactions correlate well with the populations and the νCO frequencies of the ax and eq conformers found in the gas phase. Unusually, in solution of the non-polar solvents n-C₆H₁₄ and CCl₄, the more intense higher IR carbonyl frequency can be ascribed to the ax conformer, while the less intense lower IR doublet component to the eq one. The same νCO frequency trend also holds in polar solvents, that is ν(CO)(eq)< ν(CO)(ax). However, a reversal of the ax/eq intensity ratio occurs going from non-polar to polar solvents, with the ax conformer component that progressively decreases with respect to the eq one in CHCl₃ and CH₂Cl₂, and is no longer detectable in the most polar solvent CH₃CN. The PCM method applied to compound 4 supports these findings. In fact, it predicts the progressive increase of the eq/ax population ratio as the relative permittivity of the solvent increases. Moreover, it indicates that the computed ν(CO) frequencies of the ax and eq conformers do not change in the non-polar solvents n-C₆H₁₄ and CCl₄, while the ν(CO) frequencies of the eq conformer become progressively lower than that of the ax one going from CHCl₃ to CH₂Cl₂ and to CH₃CN, in agreement with the experimental IR values. The analysis of the geometries of the ax and eq conformers shows that the carbonyl oxygen atom of the eq conformer is free for solvation, while the O[CO]…H[o-Ph] hydrogen bond that takes place in the ax conformer partially hinders the approach of the solvent molecules to the carbonyl oxygen atom. Therefore, the larger solvation that occurs in the carbonyl oxygen atom of the eq conformer is responsible for the observed and calculated decrease of the corresponding frequency. The X-ray single crystal analysis of 2 indicates that this compound adopts the most polar eq geometry in the solid. In fact, in order to obtain the largest energy gain, the molecules are arranged in the crystal in a helical fashion due to dipole moment coupling along with C-H…O and C-H…π(Ph) hydrogen bonds.