Role of Collision Geometry in Reactivity

Stanford University, Stanford CA

Investigators

Abstract

Richard N. Zare of Stanford University is supported by an award from the Chemical Structure, Dynamics and Mechanisms program to pursue studies of the role of collision geometry in chemical reactivity. Professor Zare and his postdoctoral and graduate student colleagues will examine with the most exquisite detail how elementary chemical reactions occur. Prof. Zare and his group will continue their studies of state-to-state reaction dynamics in fundamental chemical systems, seeking to understand how the precise geometry of the collision of two molecules determines the chemical outcome of this interaction. Normally, reagent molecules can be selected in particular rovibrational levels denoted by the vibrational quantum numbers v1, v2, v3, etc. and the rotational angular momentum quantum number J. However, no selection is made of the projection of the rotational angular momentum vector J on the quantization axis. Zare and his colleagues work to prepare reagents and to detect reaction products in selected M states by combining the directionality of polarized radiation for pumping and probing molecular states with the intense electric field from a synchronized nonresonant laser pulse which causes sufficiently large Stark splittings of molecular transitions that individual M states can be accessed. Their goal is to achieve nearly 100 percent transfer of population from a lower to an upper level in an M-state-selective manner, which for reaction dynamics studies would be a first. Prof. Zare will continue to serve as a mentor to a diverse group of young scientists, and will continue in his wide ranging efforts at educating the public about the importance of science. In this regard, Prof. Zare's service as a host of WONDERFEST and as a member of its board of directors is emblematic. WONDERFEST is a Bay Area celebration of science and attracts over one thousand people a year to learn about and debate upon current topics in science.