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Yeh, In-Chul;Lee, Tae-Geol;Kim, Myung-Soo
- Bulletin of the Korean Chemical Society
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- v.15 no.3
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- pp.241-245
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- 1994
A method has been developed to estimate the kinetic energy release originating from the reverse critical energy in unimolecular ion dissociation. Contribution from the excess energy was estimated by RRKM theory, the statistical adiabatic model and the modified phase space calculation. This was subtracted from the experimental kinetic energy release distribution (KERD) via deconvolution. The present method has been applied to the KERDs in $H_2$, loss from $C_6H_6^+$ and HF loss from ${CH_2CF_2}^+$. In the present formalism, not only the energy in the reaction coordinate but also the energy in some transitional vibrational degrees of freedom at the transition state is thought to contribute to the experimental kinetic energy release. Details of the methods for treating the transitional modes are found not to be critical to the final outcome. For a reaction with small excess energy and large reverse critical energy. KERD is shown to be mainly governed by the reverse critical energy.
https://doi.org/10.5012/bkcs.1994.15.3.241 인용 PDF

Jee ,Jong-Gi;Lee, Young-Hwa;Kwak, Young-Jik
- Bulletin of the Korean Chemical Society
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- v.6 no.5
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- pp.266-269
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- 1985
The dissociation constants(K) of m-chloroanilinium ion in water-ethanol mixture, where the volume percentage of water is 89.5%, were evaluated by UV-spectroscopic method at $20{\sim}50^{\circ}C$, up to 1500 bars with changing ionic strength from 0.04 to 0.10 mol $kg^{-1}$ by use of acetate buffer. K values enhance with increasing ionic strength and temperature, but decrease with elevating pressure. From K values, we obtained the partial molar volume change and some other thermodynamic parameters. From the values of enthalpy, entropy and isoequilibrium temperature (649 K), we concluded that the dissociation of m-chloroanilinium ion mentioned above is controlled by enthalpy.
https://doi.org/10.5012/bkcs.1985.6.5.266 인용 PDF

Lee, S. B.;Kang, D. H.;Park, C. Y.;Kwak, H. T.
- Bulletin of the Korean Chemical Society
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- v.16 no.2
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- pp.157-163
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- 1995
The adsorption and decomposition of NO on a stepped Pt(111) surface have been studied using thermal desorption spectroscopy and Auger electron spectroscopy. NO adsorbs molecularly in two different states of the terrace and the step, which are distinguishable in thermal desorption spectra. NO dissociates via a bent species at the step sites on the basis of vibrational spectrum data reported previously. The dissociation of NO is an activation process : the activation energy is estimated to be about 2 kcal/mol. Increase in the NO dissociation with adsorption temperature is explained by a process controlled by diffusion of the dissociated atomic nitrogen from the step to the terrace of the surface. In addition to NO and N2, the desorption peak of N2O is observed. We conclude that the formation of N2O is attributed to surface reaction of NO and N adsorbed on the surface.
https://doi.org/10.5012/bkcs.1995.16.2.157 인용 PDF