| Autor: |
Jerosimic, Stanka V., Gianturco, Franco A., Wester, Roland |
| Rok vydání: |
2017 |
| Předmět: |
|
| Zdroj: |
Physical Chemistry Chemical Physics, 2017 |
| Druh dokumentu: |
Working Paper |
| DOI: |
10.1039/C7CP05573K |
| Popis: |
The direct dynamical paths leading to Associative Detachment (AD) in the gas-phase, and specifically in the low-temperature regions of the Dark Molecular Clouds (DMC) in the ISM, or in cold trap laboratory experiments, are investigated with quantum chemical methods by using a high-level multi-reference Configuration Interaction (CI) approach that employs single and double excitations plus Davidson perturbative correction [MRSDCI(Q)] and the d-aug-cc-pV5Z basis set. The potential energy curves for H + CN- are constructed for different directions of the H partner approaching the CN- anion within the framework of the Born-Oppenheimer approximation. The present calculations found that the AD energetics at low temperature becomes favorable only along a selected range of approaching directions, thus showing that there is a preferred path of forming HCN at low temperatures, while that of forming its HNC isomer is found to be energetically forbidden. Given the existence in the ISM of different HCN/HNC ratios in different environments, we discuss the implications of our findings for selective formation of either isomer in the low-temperature conditions of the Molecular Cloud Cores. |
| Databáze: |
arXiv |
| Externí odkaz: |
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