Rotational excitation of protonated hydrogen cyanide (HCNH+) by He atom at low temperature

Autor: C. Nkem, Idriss Yacoub Halalaw, Nejm-Eddine Jaidane, Kamel Hammami, Luc C Owono Owono
Rok vydání: 2013
Předmět:
Zdroj: Astrophysics and Space Science. 349:171-179
ISSN: 1572-946X
0004-640X
DOI: 10.1007/s10509-013-1600-5
Popis: We report on ab initio coupled-cluster calculations of the interaction potential energy surface for the HCNH+–He complex. The aug-cc-pVTZ Gaussian basis, to which is added a set of bond functions placed at mid-distance between HCNH+ center of mass and He atom is used. The HCNH+ bonds length are set to their values at the equilibrium geometry, i.e., r e [HC]=1.0780 A, r e [CN]=1.1339 A and r e [NH]=1.0126 A. The interaction energy presents a global minimum located $266.9~\mathrm{cm^{-1}}$ below the HCNH+–He dissociation limit. Using the interaction potential obtained, we have computed rotational excitation cross sections in the close-coupling approach and downward rate coefficients at low temperature (T≤120 K). It is expected that the data worked out in this study may be beneficial for further astrophysical investigations as well as laboratory experiments.
Databáze: OpenAIRE