Ultracold Collisions of Fermionic OD Radicals

We discuss consequences of Fermi exchange symmetry on collisions of polar molecules at low temperatures (below 1 K), considering the OD radical as a prototype. At low fields and low temperatures, Fermi statistics can stabilize a gas of OD molecules against state-changing collisions. We find, however, that this stability does not extend to temperatures high enough to assist with evaporative cooling. In addition, we establish that a novel ``field-linked'' resonance state of OD dimers exists, in analogy with the similar states predicted for bosonic OH.