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arXiv · 1410.5873

Quantum Defect Theory for Cold Chemistry with Product Quantum State Resolution

Jisha Hazra·Brandon P. Ruzic·John L. Bohn·N. Balakrishnan
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Abstract

We present a formalism for cold and ultracold atom-diatom chemical reactions that combines a quantum close-coupling method at short-range with quantum defect theory at long-range. The method yields full state-to-state rovibrationally resolved cross sections as in standard close-coupling (CC) calculations but at a considerably less computational expense. This hybrid approach exploits the simplicity of MQDT while treating the short-range interaction explicitly using quantum CC calculations. The method, demonstrated for D+H$_2\to$ HD+H collisions with rovibrational quantum state resolution of the HD product, is shown to be accurate for a wide range of collision energies and initial conditions. The hybrid CC-MQDT formalism may provide an alternative approach to full CC calculations for cold and ultracold reactions.

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Jisha Hazra, Brandon P. Ruzic, John L. Bohn, N. Balakrishnan. 2014-10-21. Quantum Defect Theory for Cold Chemistry with Product Quantum State Resolution. https://doi.org/10.1103/physreva.90.062703

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