Sticking Lifetime of Ultracold CaF Molecules in Triplet Interactions.

A six-dimensional potential energy surface is constructed for the spin-polarized triplet state of CaF-CaF by ab initio calculations at the CCSD(T) level of theory, followed by Gaussian process interpolation. The potential is utilized to calculate the density of states for this bialkaline-earth-halogen system where we find the value 0.038 µK-1, implying a mean resonance spacing of 26 µK in the collision complex. This value implies an associated Rice-Ramsperger-Kassel-Marcus lifetime of 1.8 µs, thus predicting long-lived complexes in collisions at ultracold temperatures.