Improved temperature dependence of rate coefficients for rotational state-to-state transitions in H${}_2$O + H${}_2$O collisions

Abstract

Aim: We present an improved database of temperature dependent rate coefficients for rotational state-to-state transitions in H${}_2$O + H${}_2$O collisions. The database includes 231 transitions between the lower $para$- and 210 transitions between the lower $ortho$-states of H${}_2$O (up to $j=7$) and can be employed for cometary and planetary applications up to the temperature of 1000 K. Methods: New general method is developed and applied which permits to generate rate coefficients for excitation and quenching processes that automatically satisfy the principle of microscopic reversibility and, also, helps to cover the range of low collision energies by interpolation of cross sections between the process threshold and the computed data points. Results: It is found that in the range of intermediate temperatures, $150<T<600$ K, new rate coefficients are in good agreement with those reported earlier, but for higher temperatures, $600<T<1000$ K, the new revised temperature dependence is recommended. The low temperature range, $5<T<150$ K, is now covered, by the abovementioned interpolation of cross sections down to the process threshold.

References in corpus (6)

• Unusually High CO Abundance of the First Active Interstellar Comet
• History of the solar-type protostar IRAS16293-2422 as told by the cyanopolyynes
• A study of the distant activity of comet C/2006 W3 (Christensen) using Herschel and ground-based radio telescopes
• A SUBLIME 3D Model for Cometary Coma Emission: the Hypervolatile-Rich Comet C/2016 R2 (PanSTARRS)
• The effect of CO-H2O collisions in the rotational excitation of cometary CO
• Mixed Quantum/Classical Theory for Rotational Energy Exchange in Symmetric-Top-Rotor + Linear-Rotor Collisions and a Case Study of $\mathrm{N}{\mathrm{D}}_3+{\mathrm{D}}_2$ System

Cited by in corpus (4)

• Rate Coefficients for Rotational State-to-State Transitions in H${}_2$O + H${}_2$ Collisions as Predicted by Mixed Quantum/Classical Theory (MQCT)
• On Mixed Quantum/Classical Theory for Rotationally Inelastic Scattering of Identical Collision Partners
• Collisional Excitation in Space: Recent Advances and Future Challenges in the JWST Era
• Neural network ensemble for computing cross sections for rotational transitions in H${}_2$O + H${}_2$O collisions