The potential energy surface and chemical kinetics for the reaction of HO with CO, which is an important process in both combustion and atmospheric chemistry, were computed using high-level ab initio quantum chemistry in conjunction with semiclassical transition state theory under the limiting cases of high and zero pressure. The reaction rate constants calculated from first principles agree extremely well with all available experimental data, which range in temperature over a domain that covers both combustion and terrestrial atmospheric chemistry. The role of quantum tunneling is confirmed to be extremely important, which supports recent work by Continetti and collaborators regarding the loss of hydrogen atoms from vibrationally excited states of HOCO. A sensitivity analysis has been carried out and serves as the basis for a plausible estimate of uncertainty in the calculations.

Production of acetic acid via gas-phase hydration of ketene by water (uncatalyzed and in the presence of an additional water molecule) was theoretically characterized using high-level coupled-cluster methods, followed by a two-dimensional master equation analysis to compute thermal reaction rate constants. The results show that the formation of acetic acid quite likely occurs in high-temperature combustion of biomass, but that the rate of formation should be negligible under ambient atmospheric conditions.

Over the past several years, the Physics Education Group at the University of Washington has been developing tutorial worksheets for small-group sections for junior-level electrodynamics courses. We have observed that most of our students enter these courses with a working knowledge of static electric and magnetic fields in simple systems. However, many students have significant difficulties in transferring this knowledge to other vector fields. We first attempted to address these difficulties by having students draw analogies from basic static fields to new vector fields, but this strategy proved to be challenging for many students. Our subsequent attempt focused on familiarizing students with how the divergence and curl of a vector field defines that vector field. This approach is proving successful in enabling students to then relate this knowledge of general vector fields to understand newly introduced vector fields.