Normal mode calculations about the extended double six ring (D6R) subunit cluster model of Faujasite-type zeolites have been done by using the valence force field with reasonably adjusted force constants. We have studied for four X, Y zeolites species varying in M$_{f}$(Al/Si + Al) values. The calculated characteristic frequencies of D6R mode (${\nu}_{D_{6}R}$) and the rate of change of ${\nu}_{D_{6}R}$ with the mole fractions of aluminum, M$_{f}$ (Al/Si + Al) values agree well with Flanigen's experimental data; the experimental slope is -79 cm$^{-1}$, while the calculated slope is -82 cm$^{-1}$. Those are the improved results as compared to Blackwell's theoretical study; his predicted slope is -94 cm$^{-1}$.

The surface enhanced Raman scattering (SERS) of SCN$^{-}$ was investigated in silver sol. The addition of pyridine significantly increased SERS by as large as 70. The role of pyridine was interpreted based on the model of plasma resonance-enhanced Raman scattering.

The NMR chemical shift arising from 3d electron spin dipolar nuclear spin angular momentum interactions for a 3d$^2$ system in a strong crystal field environment of octahedral symmetry has been investigated when the fourfold axis is chosen to be our axis of quantization. The NMR shift is separated into the contribution of 1/R$^5$ and 1/R$^7$ terms. A comparision of the multipolar terms with nonmultipolar results shows that the 1/R$^5$ term contributes dominantly to the NMR shift and there is in good agreement between the exact solution and the multipolar results when R ${\ge}$ 0.25. A temperature dependence analysis may lead to the results that the 1/T$^2$ term has the dominant contribution to the NMR shift for a paramagnetic 3d$^2$ system but the contribution of the 1/T term may not be negligible.

Normal modes of solids HF, HCl and polyethylene having the exciting spectrometric phenomena have been evaluated by taking the lowest temperature phase of these species in the solid. The solids HF and HCl have the same space group as C$_{2}{\nu}$, and polyethylene has a space group with D$_{2h}$. The normal modes were obtained by the valence force field with modified force constants and a quantitative description of the normal mode is adjusted by the potential energy distribution (PED). From the PED, the most fittable force constants are also obtained. We have intended to calculate the normal modes by using the smallest size of the model and the simple computational process. To remove the edge effects being occurred in constructing the single cluster model, different from the boundary condition being generally used up to now, the idea of pseudolattice method being successfully applied to MO calculations of solid was extended to normal mode analysis in order to give the same environment for all moecules in a chosen cluster. By using the above valence force field and boundary condition, we obtain the assigned frequencies and compare those results with the results obtained by others.

The stabilities of the charge transfer complexes of pentamethyl benzene with iodine in n-hexane have been investigated by UV-spectrophotometric measurements at 25, 40 and 60$^{\circ}C$ up to 1600 bars. The equilibrium constant of the complex formation was increased with pressure while being decreased with temperature raising. Changes of volume, enthalpy, free energy and entropy for the formation of the complexes were obtained from the equilibrium constants. The red-shift at higher pressure, the blue-shift at higher temperature, and the relation between pressure and oscillator strength have been discussed by means of thermodynamic functions. In comparison with the results in the previous studies, the absolute values of ${\Delta}$V at each temperature were increased with the number of methyl groups of polymethyl benzene. However, it can be seen that both ${\Delta}$H and ${\Delta}$S show extreme behaviors in durene near atmospheric pressure but they are negatively increased with the number of methyl groups near 1600 bar. This order of the thermodynamic parameters may be a measure of the relative basicities of polymethyl benzenes toward iodine under each pressure, and these phenomena are explained in terms of a positive inductive effect and a steric hindrance effect of the polymethyl benzene molecule.

The complete neglect of differential overlap (CNDO/2) approximate wavefunctions have been applied to select the preferred signs for the dipole moment derivatives of SiH$_{4}$ and SiD$_{4}$ in conjunction with the experimental alternatives. The apparent sign discrepancy from earlier report has been identified. The effective atomic charge for hydrogen was found to be X$_{H}$/e = 0.229, more than two times larger in comparison with the values of typical hydrocarbons like CH$_{4}$. The anomalously large effective hydrogen charge was interpreted based on a quantum mechanical model as well as the value of atom anisotropy relative to effective atomic charge.

(Z)-13-Eicosen-10-one, an active component of the sex pheromone of the peach fruit moth was synthesized from 4-oxo-tridecan-1-al and heptylidenetriphenylphosphonium ylide by Wittig reaction. The key intermediate, 4-oxo-tridecan-1-al, was synthesized by three different methods. The biological activity test of the synthetic pheromone as attractant for the male peach fruit moth was tested at several districts in Korea.

The dynamic properties near (and at) a stable steady state are discussed, when a chemical system relaxes from the unstable steady state. The time-dependent correlation length for the fluctuating variable near a stable steady state is explicitly obtained by introducing the probability average for the variable satisfying the rate equation. The study is carried out about the effect of nonlinearity on the correlation length near (and at) a stable steady state.

Stereospecific [2 + 2] cycloadducts are obtained as major products when trans-cinnamonitrile derivatives are irradiated with excess tetramethylethylene. The fluorescence quenching studies, weak exciplex fluorescence, and sensitization by benzophenone suggest that this stereospecific photochemical cycloaddition reaction involves singlet exciplex intermediate formed between cinnamonitrile derivatives and tetramethylethylene.

Substituent effects of substrate and nucleophile for the reaction of substituted phenacyl tosylates with pyridines were determined conductometrically in acetonitrile. Activation parameters for these reactions were also calculated. The substituent effects in nucleophile were increased with electron-donating power of pyridines and Br${\o}$nsted linear relationship was shown. Rate constant was increased by both electron-donating and electron-attracting groups in the substrate. It seems that dissociative S$_{N}$2 ("loose" transition state) mechanism is operating in the case of electron-donating substituents while associative S$_{N}$2 ("tight" transition state) mechanism is operative in the case of electron-attracting substituents.

Quantum chemical calculations were carried out to explain how the electronic states of some series compounds vary with metabolic activation. Compounds studied included aromatic amines and amides, polycyclic hydrocarbons, and a few alkylating agents that do not require metabolic activation. The 1, 2 and 4 positions forming the trans-butadiene frame of a molecule, henceforth referred to as "the trans 1, 2, 4 region", have seen to be important positions for the prediction of carcinogenic activity of these compounds. It is also evident that their electrophilic properties increase with metabolic activation. That is the sum of ${\pi}$-electron densities of the trans 1, 2, 4 region in the lowest unoccupied molecular orbital (LUMO) has been found to increase in the order of precarcinogens < proximate-ones < the carbocation ultimate-ones. This is consistent with the fact that chemical carcinogens become more strongly electrophilic with activating. This region not only provides a unified view of structurally diverse carcinogens, but also predicts uniformity in their reactive sites. Accordingly, we suggest that an understanding of the trans 1, 2, 4 region would be helpful in elucidating the mechanism of carcinogenesis.

A revised simple method is proposed to calculated the ionicities and bond energies of diatomic molecules including hydrogen halides, interhalogen compounds, alkali hydrides, and alkali halides. The relative nuclear quadrupole coupling constants are evaluated to check the further validity of this method. It is shown that calculated values are consistent with available experimental values.

3-Aminopropylsilated silica gel bound hemin, biliverdin, and bilirubin were synthesized by reacting 3-aminopropyl silated silica gel with hemin, biliverdin and bilirubin respectively. The aspects of binding of bilirubin to amino group of 3-aminopropylsilated silica gel were studied using the above synthetic silica immobilized hemin, biliverdin and bilirubin, and oxodipyrromethene.

The oxidation of hydrazobenzene by oxygen in methanol solution is catalysed by Co(3MeOsalen) which is a synthetic oxygen carrier. The products are trans-azobenzene and water. The rate of the reaction has been studied spectrophotometrically and the rate law established. A mechanism involving a ternary complex of catalyst, hydrazobenzene and oxygen has been proposed.

Stereospecific coordination of racemic 2,3-diaminobutane has been observed in the reaction with platinum(Ⅱ) complexes of optically active 6,6'-dimethyl-2,2'-diaminobiphenyl. The reaction between [Pt (R-dmdabp) Cl$_{2}$] (R-dmdabp is R-6,6'-dimethyl-2,2'-diaminobiphenyl) and unresolved bn (bn is 2,3-diaminobutane) has yielded [Pt(R-dmdabp)-(R-bn)] Cl$_{2}$ only, while the reaction of [Pt(S-dmdabp)Cl$_{2}$] with unresolvd bn has yielded [Pt(S-dmdabp) (S-bn)]Cl$_{2}$ only. On the other hand, the standard [Pt(R-dmdabp) (R-bn)] Cl$_{2}$ complex has been independently prepared from the reaction of [Pt(R-dmdabp)Cl$_{2}$] with R-bn, and the standard [Pt(S-dmdabp) (S-bn)] Cl$_{2}$ from the reaction of [Pt(S-dmdabp)Cl$_{2}$] with S-bn. The stereospecific behavior of the racemic 2,3-diamino-butane is thus confirmed from the comparison of these Pt(Ⅱ) complexes prepared using racemic bn with the standard Pt(Ⅱ) complexes prepared using R-bn or S-bn.