Ultracold Rb-OH collisions and prospects for sympathetic cooling
  We have computed ab inito cross sections for cold collisions of Rb atoms with OH radicals. We predict collision rate constants of order 10^{-11} cm^3/s at temperatures in the range 10-100 mK at which molecules have already been produced experimentally. However, we also find that in these collisions the molecules have a strong propensity for changing their internal state, which could make sympathetic cooling of OH in a Rb buffer gas problematic in magnetostatic or electrostatic traps. 
M. Lara, J. L. Bohn, D. Potter, P. Soldan, and J. Hutson