It is now well known that mesoporous inorganic materials with extremely high surface areas and ordered mesostructure can be synthesized through sol-gel reactions of metal alkoxides in the presence of molecular assemblies of surfactants or related structure directing substances. [1±4] The original method, developed by scientists at Mobil Oil Research and Development, [1] has lead to extensive applications of these materials as catalyst supports and chromatographic resins. [4] The mechanism of organization of such a mesostructure involves electrostatic interactions and charge matching between micellar assemblies of quaternary ammonium cations (S + ) and anionic silicate oligomer species (I ± ).In many applications of mesoporous materials, functionalization of silanol groups on the surfaces of the materials are required. [5±7] Presently, extensive research is being conducted to develop procedures to introduce functional silane ligands into the surfaces of the ordered mesoporous materials. For example, Liu and coworkers [6] have recently developed new and more effective mesoporous sorbents for the removal of toxic metal ions by coating surfaces of the hexagonally packed mesoporous silica with organic functional groups to enhance the affinity of the mesoporous sorbents for toxic metal ions. Similar sorbents have also been described by Mercier and Pinnavaia. [7] The generally accepted mechanism for the direct coating method involves the initial hydrolysis of siloxane groups in the functional silane ligand followed by condensation with the surface silanol groups to produce ligands that are covalently bonded or ªtetheredº to the surfaces. Drawbacks associated with this direct coating method are: 1) the requirement of timeconsuming (>24 h) syntheses under reflux and 2) low loading of functional silane ligands. In this communication we _______________________ ± [*] Dr.

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Technology (KIST); more than one hundred participants attended this symposium. The main topics of the symposium were the experimental and theoretical aspects of nanoscience, biological science, and related materials to develop applications. The organizing committee proposed to publish these high-quality papers in a special issue of Research on Chemical Intermediates.During the last decade, the research in developing new materials has become an extremely interesting research area. The symposium included organic synthesis for theoretical investigation of frontier materials. The information provided could open the door to the design of new materials.This special issue includes 17 papers, which were presented at the symposium. We would like to thank all of the authors who contributed their recent research results in this special issue of Research on Chemical Intermediates. We also express our deep gratitude to all the reviewers for their effort and expertise in reviewing the manuscripts.

Molecular dynamics, a computational technique aiming to describe the time-dependent movement of molecules, has been applied to study the sorption kinetics of volatile organic contaminants in soil organic matter. The molecular dynamics simulation results obtain reasonably accurate estimates of diffusion rates and activation energy of the penetration of a volatile organic compound molecule into a model humic substance. The sorption rate of toluene to humic acid decreases with the density of the humic acid matrix and increases with temperature. All the present results indicate that the sorption of toluene into humic acid is mainly diffusion controlled. Finally, the present studies have shown that molecular dynamics of volatile organic compounds in humic substances yields meaningful results, which help in the understanding of diffusion at the molecular level and which facilitate the problem-solving capability for removing the contaminants from the soils.

Density functional theory (DFT)-based molecular dynamics (DFTMD) simulations in combination with a Fourier transform of dipole moment autocorrelation function are performed to investigate the adsorption dynamics and the reaction mechanisms of self-coupling reactions of both acetylide (H3C-C(β)≡C(α) (ads)) and ethyl (H3C(β)-C(α)H2(ads)) with I(ads) coadsorbed on the Ag(111) surface at various temperatures. In addition, the calculated infrared spectra of H3C-C(β)≡C(α)(ads) and I coadsorbed on the Ag(111) surface indicate that the active peaks of -C(β)≡C(α)- stretching are gradually merged into one peak as a result of the dominant motion of the stand-up -C-C(β)≡C(α)- axis as the temperature increases from 200 K to 400 K. However, the calculated infrared spectra of H3C(β)-C(α)H2(ads) and I coadsorbed on the Ag(111) surface indicate that all the active peaks are not altered as the temperature increases from 100 K to 150 K because only one orientation of H3C(β)-C(α)H2(ads) adsorbed on the Ag(111) surface has been observed. These calculated IR spectra are in a good agreement with experimental reflection absorption infrared spectroscopy results. Furthermore, the dynamics behaviors of H3C-C(β)≡C(α)(ads) and I coadsorbed on the Ag(111) surface point out the less diffusive ability of H3C-C(β)≡C(α)(ads) due to the increasing s-character of Cα leading to the stronger Ag-Cα bond in comparison with that of H3C(β)-C(α)H2(ads) and I coadsorbed on the same surface. Finally, these DFTMD simulation results allow us to predict the energetically more favourable reaction pathways for self-coupling of both H3C-C(β)≡C(α)(ads) and H3C(β)-C(α)H2(ads) adsorbed on the Ag(111) surface to form 2,4-hexadiyne (H3C-C≡C-C≡C-CH3(g)) and butane (CH3-CH2-CH2-CH3(g)), respectively. The calculated reaction energy barriers for both H3C-C≡C-C≡C-CH3(g) (1.34 eV) and CH3-CH2-CH2-CH3(g) (0.60 eV) are further employed with the Redhead analysis to estimate the desorption temperatures approximately at 510 K and 230 K, respectively, which are in a good agreement with the experimental low-coverage temperature programmed reaction spectroscopy measurements.