# Adiabatic theory for anisotropic cold molecule collisions.

@article{Pawlak2015AdiabaticTF,
title={Adiabatic theory for anisotropic cold molecule collisions.},
author={Mariusz Pawlak and Yuval Shagam and Edvardas Narevicius and Nimrod Moiseyev},
journal={The Journal of chemical physics},
year={2015},
volume={143 7},
pages={
074114
}
}
• M. Pawlak, +1 author N. Moiseyev
• Published 21 August 2015
• Chemistry, Medicine
• The Journal of chemical physics
We developed an adiabatic theory for cold anisotropic collisions between slow atoms and cold molecules. It enables us to investigate the importance of the couplings between the projection states of the rotational motion of the atom about the molecular axis of the diatom. We tested our theory using the recent results from the Penning ionization reaction experiment (4)He(1s2s (3)S) + HD(1s(2)) → (4)He(1s(2)) + HD(+)(1s) + e(-) [Lavert-Ofir et al., Nat. Chem. 6, 332 (2014)] and demonstrated that… Expand
17 Citations

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#### References

SHOWING 1-10 OF 27 REFERENCES
Magnetic-field effects in ultracold molecular collisions
• Physics
• 2002
We investigate the collisional stability of magnetically trapped ultracold molecules, taking into account the influence of magnetic fields. We compute elastic and spin-state-changing inelastic rateExpand
Quantum theory of reactive collisions for 1/r(n) potentials.
• Physics, Medicine
• Physical review letters
• 2013
A general quantum theory for reactive collisions involving power-law potentials (-1/r(n)) valid from the ultracold up to the high-temperature limit and agrees well with recent merged beam experiments on Penning ionization. Expand
Ultracold Rb-OH collisions and prospects for sympathetic cooling.
• Materials Science, Physics
• Physical review letters
• 2006
It is found that in cold collisions of Rb atoms with OH radicals 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. Expand
Universal rate constants for reactive collisions of ultracold molecules.
• Physics, Medicine
• Physical review letters
• 2010
A simple quantum-defect model gives analytic expressions for the complex scattering length and threshold collision rates of ultracold molecules and gives universal rate constants for s- and p-wave collisions that are independent of short-range dynamics. Expand
Observation of orbiting resonances in He((3)S(1)) + NH3 Penning ionization.
• Chemistry, Physics
• The Journal of chemical physics
• 2015
The observation of shape resonances in the reactive scattering of a polyatomic molecule, NH3, is presented and no clear signature of the orbiting resonances is visible in the branching ratio between NH3 (+) and NH2 (+) formation. Expand
Quantum theory of chemical reactions in the presence of electromagnetic fields.
• Chemistry, Physics
• The Journal of chemical physics
• 2008
The theory is applied to examine the effects of electric fields on the chemical reactions of LiF molecules with H atoms and HF molecules with Li atoms at low temperatures and shows that electric fields may enhance the probability of chemical reactions and modify reactive scattering resonances by coupling the rotational states of the reactants. Expand
Controlling electronic spin relaxation of cold molecules with electric fields.
• Physics, Medicine
• Physical review letters
• 2006
It is suggested that electric fields may affect chemical reactions through inducing nonadiabatic spin transitions and facilitate evaporative cooling of molecules in a magnetic trap. Expand
Observation of the isotope effect in sub-kelvin reactions.
It is demonstrated that measurements of a single isotope are insufficient to constrain ab initio calculations, making the kinetic isotope effect in the cold regime necessary to remove ambiguity among possible potential energy surfaces. Expand
Adiabatic channel capture theory applied to cold atom–molecule reactions: Li + CaH $\to$ LiH + Ca at 1K
• Physics
• 2015
We use quantum and classical adiabatic capture theories to study the chemical reaction Li + CaH LiH + Ca. Using a recently developed ab initio potential energy surface, which provides an accurateExpand
Rotational excitation of H2O by para-H2 from an adiabatically reduced dimensional potential.
• Chemistry, Medicine
• The Journal of chemical physics
• 2012
A good agreement is found between the reduced adiabatic calculations and the 5D exact calculations, with an impressive time saving and memory gain, which seems very promising for scattering studies involving the excitation of a heavy target molecule by a light molecular projectile. Expand