Factors affecting the kinetic isotope effects (KIEs) of the gas-phase S(N)2 reactions and their temperature dependence have been analyzed using the ion-molecule collision theory and the transition state theory (TST). The quantum-mechanical tunneling effects were also considered using the canonical variational theory with small curvature tunneling (CVT/SCT). We have benchmarked a few ab initio a...

The formation of charge-transfer complexation between dibenzo-15-crown-5 (DB15C5) and benzo-12-crown-4 (B12C4) (Donor) and iodine is investigated spectrophotometrically in three chlorinated solvents,chloroform, dichloromethane (DCM) and 1,2-dichloroethane (DCE) solution at 25°C. The change in polarityof the solvent also doesn’t affect the stoichiometry of the complexes. Values of formation cons...

A computational approach that has been used extensively in the last two decades for Hall thruster simulations is to solve a diffusion equation and energy conservation law for the electrons in a direction that is perpendicular to the magnetic field, and use discrete-particle methods for the heavy species. This “hybrid” approach has allowed for the capture of bulk plasma phenomena inside these th...

Graft copolymers of acrylamide on carboxymethyl cellulose (d.s 0.4-0.5) were prepared by the use of ceric ion, ceric ion/reductant molecule initiator systems in aqueous medium. The graft copolymers were characterized by IR spectroscopy. The extent of graft copolymerisation was measured in terms of grafted chains as a function of both ceric ion and ceric ion/reductant molecule concentrations. It...

Aerosol particle reactions with vapor molecules and molecular clusters are often collision rate limited, hence determination of particle-vapor molecule and particle-molecular cluster collision rates are of fundamental importance. These collisions typically occur in the mass transfer transition regime, wherein the collision kernel (collision rate coefficient) is dependent upon the diffusive Knud...

The parametric resonant behavior of ions inside a linear rf ion trap is studied both theoretically and experimentally. Theoretically, the resonant motion of ions inside an ideal ion trap is described by approximating the trapping rf field as a harmonic pseudopotential with the ions being excited by an additional quadrupolar ac voltage. The resulting damped Mathieu equation is studied and the re...

The charge-transfer complexation reaction between iodine and dibenzo- 18-crown- 6 (DB18C6) has been studied spectrophotometrically in chloroform solution at different temperatures. The resulting donor-acceptor complex was formulated as (DB 18C6…I )I . The spectrophotometric results , as well as the conductivity measurements, indicated that the gradual release of tiiodide ion from its contac...