Electrochemical reduction of nitrobenzene and substituted nitrobenzenes on lead electrode was studied by galvano-static measurements and cyclic voltammetry in basic ethanol-water solvents. Nitroso compounds or hydroxylamines were detected as the main reduction product depending on the potential. Mechanisms of production and further reduction of substituted and unsubstituted nitrosobenzenes are deduced from Tafel slope, pH dependence and reaction order. The reduction of most of the substituted nitrobenzenes to corresponding nitrosobenzene derivatives seemed to follow the reaction mechanism of nitrobenzene reduction with a few exceptions. A Hammett type relationship between the magnitude of the reduction current and the kinds of substituents was found with the ${\rho}$ value of 0.54.

A new potential function based on spectroscopic results for diatomic molecules is presented and applied to the hydrogen bonding systems. The potential energy of interaction is supposed to have electrostatic, polarization, dispersion, repulsion and effective charge-transfer contributions. Estimates of the effective charge-transfer quantity have been made based on the average charge of the proton donor and the acceptor atoms. For dimers such as water, methanol, acetic acid and formic acid, the vibrational stretching frequencies and dimerization energies are calculated and dicussed in connection with Badger-Bauer rule.

Alkyl and alkenyl substituent effects on nonbonded interactions of hexatriene were examined using CNDO/2 method. The results showed that: (1) rapid rate of thermal electrocyclization of 3-vinyl hexa-1, 3, 5-triene is due to increased overlap population between atom pair reacting resulting from strong electron repelling interaction of vinly group on the triene moiety; (2) stability of a conformer is determined by additive effect of composite ${\pi}$ structures; (3) a substituent on positions 2 and 3 increases the HOMO AO coefficient of sites 1 and 4 considerably and activates interactions with these sites.

Thermodynamic properties such as sublimation pressures, enthalpies and entropies of sublimation, enthalpies and entropies of solid krypton and xenon are calculated from $0{\circ}K$ to the triple point, using the vacancies-in-solid model. The Mie-Lennard-Jones 12,6 potential in uniform potential field is used. The results are compared with the calorimetric and sublimation pressure values, and are in a good agreement with the available calorimetric and sublimation pressure values.

Theoretical studies of the sodium cation binding and the isotope hydration effects on the static model compound B-DNA have been qualitatively elucidated by using empirical potential energy functions. In the first place, the sodium cations bound to phosphate anions and their hydration scheme have been optimized and have given a reasonable agreement with other theoretical results and experimental studies. In the second stage, the isotope effect on the hydration through the substitution of $D_2O\;for\;H_2O$ has been carried out by the same procedure. The stabilization of B-DNA has been explained and compared in terms of the sodium cation binding to phosphate anions and its hydration in both cases of $H_2O\;and\;D_2O$.

Chemical shift values of ${\alpha}$-proton of trans- and cis-methyl cinnamates are well correlated with ${\sigma}({\sigma}_1,\; {{\sigma}_R}^{\alpha})$, and (F, R) (r=0.999-0.879). It is observed that (1) the degree of variation of ${\delta}H_{\alpha}$ value by varying the substituents in trans-cinnamates is similar to that of cis-cinnamates $({\rho}_{trans}=0.296,\;{\rho}_{cis}=0.2840, (2) resonance contribution is larger in the trans-cinnamates than that in the cis-cinnamates, but inductive contribution is reversed, (3) for m-substitued derivatives, resonance contribution is very small compared to that for p-substituted derivatives.