A computational study using density functional theory is carried out to investigate the reaction mechanism of ethanol steam reforming on Co(0001) surfaces. The adsorption properties of the reactant, possible intermediates, and products are carefully examined. The reaction pathway and related transition states are also analyzed. According to our calculations, the reforming mechanism primarily consisting of dehydrogenation steps of ethanol, ethoxy, methanol, methoxy, and formic acid, is feasible on Co(0001) surfaces. It is also found that the reaction of formaldehyde yielding formic acid and hydrogen may not be an elementary reaction. The dehydrogenation of ethoxy possesses the highest barrier and is accordingly identified as the rate-determining step.

Density functional theory is employed to characterize the infrared and terahertz spectra of an explosive molecular species, RDX, deposited over an aluminum surface, modeled as a planar cluster of Al(16). Changes in the inter- and intramolecular vibrational modes are systematically analyzed starting from the isolated monomer, dimer, and tetramer and then considering the interactions of the monomer with an Al plate. The results are compared to available experimental information for RDX films on Al surfaces. It is found that the RDX molecule changes conformation because of the interaction with the model Al surface, becoming closer to an AAA conformation with the three NO(2) groups in nearly axial positions. The calculated spectra serve as an initial guideline to interpret the main peaks of previously reported RDX films on Al.

The synthesis of mono‐N adducts of 5‐methyl‐1,3,5‐dithiazinane (1) with Al(CH3)3, Al(CH3)2Cl, AlCl3, AlBr3 (5−8), a bis‐N adduct with InCl3 (9), and the corresponding dithiazinanium salts with the anions AlBr4−, AlCl4−, GaCl4− and BCl4− (10−14) are reported. Compounds 5−7 adopt a preferred conformation in solution at room temperature and 8 at −10 °C. ΔG≠ values for the ring inversion were calculated for 5−8. Compounds 6−14 were studied by single‐crystal X‐ray diffraction. The solution and solid‐state analyses showed that the rings are present in all cases in a chair conformation. In compounds 5−8 the tetrahedral aluminum atom is found in an equatorial position. In the indium compound 9 the metal atom has a tbp geometry. For dithiazinanium rings 10−14 dipolar intra‐ and intermolecular interactions between halogen atoms and C−H and N−H are reported. Two different conformations for the N−CH3 were found in compound 14. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

Structural and conformational studies performed by 1 H-, 11 B-, derivatives produced the axial borane compounds. Rearrangement reactions of the adducts gave the first 13 C-, two-dimensional, and variable-temperature NMR spectroscopy of borane and chloroborane adducts of 1,3,5-examples of chloroboracyclohexanes bearing boron and nitrogen atoms as stable stereogenic centers. BClH 2 and heterocyclohexanes and their rearrangement products, boracyclohexanes, are reported. N-Methyl derivatives gaveBCl 2 H adducts were found to be more stable towards ring rearrangement than the corresponding N-BH 3 analogs. equatorial N-borane adducts whereas the N-isopropyl

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