The HCO⁺-H₂ van der Waals interaction: potential energy and scattering
1Université Grenoble Alpes, IPAG, F-38000 Grenoble, France and CNRS, IPAG, F-38000 Grenoble, France.
The Journal of Chemical Physics
|November 17, 2014
Summary
We calculated the interaction potential between the formyl cation (HCO+) and hydrogen molecule (H2). Our quantum scattering calculations accurately predict experimental pressure broadening measurements.
Area of Science:
- Physical Chemistry
- Chemical Physics
- Computational Chemistry
Background:
- Understanding molecular interactions is crucial for fields like astrochemistry.
- The interaction between HCO+ and H2 is important for interstellar medium chemistry.
Purpose of the Study:
- To compute the four-dimensional interaction potential energy surface for HCO+–H2.
- To perform quantum scattering calculations for low-lying rotational levels of HCO+ and H2.
Main Methods:
- Ab initio energies were calculated using coupled-cluster single double triple (CCSD(T)) theory.
- Basis Set Superposition Errors (BSSE) were corrected.
- A spherical basis set was used to fit the ab initio points for quantum scattering.
- Coupled channels scattering calculations were performed.
Main Results:
- The HCO+–H2 interaction potential was computed.
- Elastic and rotationally inelastic scattering cross-sections were calculated.
- Results were compared with previous computations involving He and H2.
- The computed results show good agreement with experimental pressure broadening measurements.
Conclusions:
- The computed HCO+–H2 potential and scattering data are reliable.
- This work provides valuable data for astrochemical models.
- The agreement with experimental data validates the computational methods used.
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