The rotational excitation of HCN and HNC by He: new insights on the HCN/HNC abundance ratio in molecular clouds

@article{Sarrasin2010TheRE,
  title={The rotational excitation of HCN and HNC by He: new insights on the HCN/HNC abundance ratio in molecular clouds},
  author={E. Sarrasin and Dahmani Abdallah and Michael Wernli and A. Faure and Jos{\'e} Cernicharo and F. Lique},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2010},
  volume={404},
  pages={518-526}
}
Modelling of molecular emission from interstellar clouds requires the calculation of rates for excitation by collisions with the most abundant species. The present paper focuses on the calculation of rate coefficients for rotational excitation of the hydrogen cyanide (HCN) and hydrogen isocyanide (HNC) molecules in their ground vibrational state in collision with He. The calculations are based on new two-dimensional potential energy surfaces obtained from highly correlated ab initio… 

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