Abstract A fundamental question in the study of chemical reactions is how reactions proceed at a collision energy close to absolute zero. This question is no longer hypothetical: quantum degenerate gases of atoms and molecules can now be created at temperatures lower than a few tens of nanokelvin. Here we consider the benchmark ultracold reaction between, the most-celebrated ultracold molecule, KRb and K. We map out an accurate ab initio ground-state potential energy surface of the K 2 Rb complex in full dimensionality and report numerically-exact quantum-mechanical reaction dynamics. The distribution of rotationally resolved rates is shown to be Poissonian. An analysis of the hyperspherical adiabatic potential curves explains this statistical character revealing a chaotic distribution for the short-range collision complex that plays a key role in governing the reaction outcome.Abstract A fundamental question in the study of chemical reactions is how reactions proceed at a collision energy close to absolute zero. This question is no longer hypothetical: quantum degenerate gases of atoms and molecules can now be created at temperatures lower than a few tens of nanokelvin. Here we consider the benchmark ultracold reaction between, the most-celebrated ultracold molecule, KRb and K. We map out an accurate ab initio ground-state potential energy surface of the K 2 Rb complex in full dimensionality and report numerically-exact quantum-mechanical reaction dynamics. The distribution of rotationally resolved rates is shown to be Poissonian. An analysis of the hyperspherical adiabatic potential curves explains this statistical character revealing a chaotic distribution for the short-range collision complex that plays a key role in governing the reaction outcome.

Nature CommunicationsJul 19, 201781 citations

Ultracold chemistry with ground-state KRb molecules

Brian Neyenhuis, Silke Ospelkaus, Kang-Kuen Ni +6 more

Bulletin of the American Physical SocietyMay 27, 20100 citations

Product-state control of bi-alkali-metal chemical reactions

Edmund Meyer, John L. Bohn

We consider ultracold, chemically reactive scattering collisions of the diatomic molecules KRb. When two such molecules collide in an ultracold gas, we find that they are energetically forbidden from reacting to form the trimer species ${\mathrm{K}}_{2}\mathrm{Rb}$ or ${\mathrm{Rb}}_{2}\mathrm{K}$ , and hence can only react via the bond-swapping reaction $2\mathrm{KRb}\ensuremath{\rightarrow}{\mathrm{K}}_{2}+{\mathrm{Rb}}_{2}$. Moreover, the tiny energy released in this reaction can in principle be set to zero by applying electric or microwave fields, implying a means of controlling the available reaction channels in a chemical reaction.We consider ultracold, chemically reactive scattering collisions of the diatomic molecules KRb. When two such molecules collide in an ultracold gas, we find that they are energetically forbidden from reacting to form the trimer species ${\mathrm{K}}_{2}\mathrm{Rb}$ or ${\mathrm{Rb}}_{2}\mathrm{K}$, and hence can only react via the bond-swapping reaction $2\mathrm{KRb}\ensuremath{\rightarrow}{\mathrm{K}}_{2}+{\mathrm{Rb}}_{2}$. Moreover, the tiny energy released in this reaction can in principle be set to zero by applying electric or microwave fields, implying a means of controlling the available reaction channels in a chemical reaction.

arXiv:1004.3317Physical Review AOct 14, 201033 citations

{\mathrm{K}}_{2}\mathrm{Rb}

{\mathrm{Rb}}_{2}\mathrm{K}

, and hence can only react via the bond-swapping reaction $2\mathrm{KRb}\ensuremath{\rightarrow}{\mathrm{K}}_{2}+{\mathrm{Rb}}_{2}$. Moreover, the tiny energy released in this reaction can in principle be set to zero by applying electric or microwave fields, implying a means of controlling the available reaction channels in a chemical reaction.