Silylamine reversible ionic liquids were designed to achieve specific physical properties in order to address effective CO₂ capture. The reversible ionic liquid systems reported herein represent a class of switchable solvents where a relatively non-polar silylamine (molecular liquid) is reversibly transformed to a reversible ionic liquid (RevIL) by reaction with CO₂ (chemisorption). The RevILs can further capture additional CO₂ through physical absorption (physisorption). The effects of changes in structure on (1) the CO₂ capture capacity (chemisorption and physisorption), (2) the viscosity of the solvent systems at partial and total conversion to the ionic liquid state, (3) the energy required for reversing the CO₂ capture process, and (4) the ability to recycle the solvents systems are reported.

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Experimental study of the dynamics of the H+D2→HD+D reaction at collision energies of 0.55 and 1.30 eV J. Chem. Phys. 81, 1298 (1984; 10.1063/1.447762 H+D2 reaction dynamics. Determination of the product state distributions at a collision energy of 1.3 eV J. Chem. Phys. 80, 4142 (1984); 10.1063/1.447242The dynamics of the reaction D+ 2+F(2 P)→FD++D at kinetic energies between 0.002 and 30 eV Absolute total reaction cross sections and product kinetic energy distributions have been measured for the reaction Dt + e-.CD+ + D over the range of initial kinetic energies between 0.002 and 14 eV. At very low collision energies, the reaction cross section is accurately proportional to the capture cross section calculated for n approaches of the reactants, taking into account the long-range charge-quadrupole and charge-induced dipole interactions. About 37% of close collisions on n surfaces lead to CD+ + D reaction products.Reactions on ~ surfaces are inhibited at low kinetic energies by a strongly repulsive charge-quadrupole interaction at large separations. The reaction is direct at all kinetic energies, with the CD+ product scattered preferentially in the direction of the incident C atom. The reaction is extremely exoergic, and the CD+ product is formed with an internal energy very near its dissociation limit over a large range of collision energies. Although the experimental results do not give direct information on the electronic state pathways to the observed products (except that the reactants approach asymptotically on n surfaces), the electronic state correlations suggest a low-energy adiabatic pathway to the CH+ en) first excited state ofthe products, which is consistent with both the measured values of the reaction cross sections and the reaction energetics.

Density functional theory (DFT) calculations were used to study the mechanism of CO 2 hydrolysis by Zn-(1,5,9-triazacyclododecane) and Zn-cyclam and evaluate the associated thermodynamic and kinetic parameters. Microkinetic models were then built based on the kinetics and thermodynamics derived from first principles. Both catalysts showed very similar behavior to Zn-cyclen, which we have reported previously, but with multiple distinctions. The intrinsic reaction rate constants for Zn-(1,5,9-triazacyclododecane) and Zn-cyclam were calculated to be 2693 and 4623 M −1 s −1 , respectively, which is in reasonable agreement with experimental values reported or estimated. The CO 2 adsorption step was found to be a ratelimiting step for all three catalysts. Zn-cyclam has the lowest barrier for this step due to the highest pK a or nucleophilicity of the Zn-OH − form, and , therefore, the highest intrinsic activity. However, the observed reaction rate constant also depends on the availability of the catalyst. The decrease in the observed reaction rate constant over 0-12 ms was ascribed to the decrease in the concentration of the catalytic form, Zn-OH − , which was primarily converted to Zn-HCO 3 − . The reaction rate constant of Zn-cyclam dropped much faster than those of Zn-cyclen and Zn-(1,5,9-triazacyclododecane) due to lower energy of the Zn-HCO 3 − form. The conversion of CO 2 at 1000 ms as a function of pH was calculated to compare the relative activity of these catalysts, and Zn-cyclen was found to be the best catalyst.