Has anyone seen today’s issue of Science? There is a research paper by Shannon Yan and colleagues “Do Vibrational Excitations of CHD3 Preferentially Promote Reactivity Toward the Chlorine Atom?” I had a difficult time following the authors – physical-molecular chemistry is not my strongest field, but nevertheless …
The study shows the energy of the moving molecules can unexpectedly promote a chemical reaction as effectively as the energy from within the chemical bonds. Until now, there has been a general assumption characterized as the Polanyi rules that the energy dynamics of reactions of small molecules with two and three atoms were simple – the vibrational energy of the bonds determines reactivity. However, a series of precisely controlled molecular collision experiments now challenges this model.
The P. Chem. scientist discovered that when CHD3 collides with Cl atoms to form CD3 and HCl, translational energy (produced by the movement of molecules in relation to each other) promoted the reaction as effectively as selective excitation of the C-H stretch vibration.