Molecular collisions at very low temperature

We have reported a number of investigations in which a newly developed collisional cooling method was used to investigate collisional processes between gas phase atoms and molecules at very low temperatures.1-7 In these studies the molecules are effectively in thermodynamic equilibrium with their collision partners, but at temperatures far below their freezing points. Used in conjunction with conventional equilibrium cells, measurements over the entire 1 - 1000 K region can be made. This range makes possible both the observation of new collision phenomena at low temperature and the study of collisions over a wide enough range to consider the collisions spectroscopically.