http://dspace.nbuv.gov.ua:80/handle/123456789/128484 Thu, 16 Apr 2026 20:57:37 GMT 2026-04-16T20:57:37Z http://dspace.nbuv.gov.ua:80/bitstream/id/382169/ http://dspace.nbuv.gov.ua:80/handle/123456789/128484 http://dspace.nbuv.gov.ua:80/handle/123456789/128993 4th International Conference on Cryocrystals and Quantum Crystals (CC 2002) Bondybey, V.E.; Savchenko, E.V. Wed, 01 Jan 2003 00:00:00 GMT http://dspace.nbuv.gov.ua:80/handle/123456789/128993 2003-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/128945 Monte Carlo simulations of krypton adsorption in nanopores: Influence of pore wall heterogeneity on the adsorption mechanism Kuchta, Bogdan; Llewellyn, Philip; Denoyel, Renaud; Firlej, Lucyna We present molecular simulation results of the adsorption of krypton in a model of MCM-41 mesoporous material. The adsorption isotherm and adsorption enthalpies have been studied at 77 K. The comparison of experimental and simulation data allows us to analyze how the available interaction models (Kr–Kr and Kr–walls) are able to reproduce the experimental situation. The role of the heterogeneous interactions versus homogenous model is studied and compared with the previous simulation results of nitrogen adsorption in MCM-41. The results show that a model of ideal cylindrical pores gives qualitatively and quantitatively different results. A distribution of the adsorption sites must exist to explain the loading at low pressure (below capillary condensation). Such distribution in MCM-41 is a consequence of non-homogenous walls that contain a wide variety of attractive sites ranging from weakly attractive silica-type to highly attractive regions. In our simulations, the MCM-41 structure is modeled as an amorphous array of oxygen and silicon atoms, each one interacting with an adsorptive atom via the atom-atom potential. The distribution of the adsorption sites is merely a consequence of local atomic structure. Such a model of the wall reproduces the smooth increase in loading seen experimentally. Wed, 01 Jan 2003 00:00:00 GMT http://dspace.nbuv.gov.ua:80/handle/123456789/128945 2003-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/128944 Activation spectroscopy of electronically induced defects in solid Ne Grigorashchenko, O.N.; Rudenkov, V.V.; Khizhnyi, I.V.; Savchenko, E.V.; Frankowski, M.; Smith-Gicklhorn, A.M.; Beyer, M.K.; Bondybey, V.E. Thermally stimulated luminescence (TSL) and thermally stimulated exoelectron emission (TSEE) methods were used in combination with cathodoluminescence to probe electronically induced defects in solid Ne. The defects were generated by a low energy electron beam. For spectroscopic study we used Ar* centers in Ne matrix as a model system. At a temperature of 10.5 K a sharp decrease in the intensity of "defect" components in the luminescence spectrum was observed. From the analysis of the corresponding peak in the TSL and TSEE yields the trap depth energy was estimated and compared with available theoretical calculations. The obtained data support the model suggested by Song, that stable electronically induced defects have the configuration of second-neighbour Frenkel pairs. Wed, 01 Jan 2003 00:00:00 GMT http://dspace.nbuv.gov.ua:80/handle/123456789/128944 2003-01-01T00:00:00Z http://dspace.nbuv.gov.ua:80/handle/123456789/128943 Matrix-isolation FTIR study of azidoacetone and azidoacetonitrile Frankowski, Marcin; Algarra, Manuel; Rodrigues, Paula; Barros, Maria T.; D.S. Cordeiro, M. Natália; Fox, Brigitte S.; Smith-Gicklhorn, Alice M.; Beyer, Martin K.; Costa, Maria L.; Bondybey, Vladimir E. Azidoacetonitrile (N₃CH₂CN) and azidoacetone (N₃CH₂COCH₃) were studied by matrix-isolation FTIR spectroscopy in solid neon, argon and nitrogen. The IR spectra calculated using the density fuctional theoretical method are discussed in comparison with the experimental data. Significant broadening of the recorded azide bands indicate an awkward fit of these compounds into the solid environment. The strongest absorption is observed for both compounds in the regions of asymmetric and symmetric stretches of the N₃ azide group. Strong band splittings in the N₃ asymmetric stretch region can be most likely explained by very strong Fermi resonances with the CN stretch and combinations and overtones of the numerous lower frequency vibrational modes. Wed, 01 Jan 2003 00:00:00 GMT http://dspace.nbuv.gov.ua:80/handle/123456789/128943 2003-01-01T00:00:00Z