Detectable interstellar anions: Examining the key factors.

Area of Science:

• Astrochemistry
• Quantum Chemistry
• Astrophysics

Background:

• Radiative electron attachment (REA) is a key process for forming interstellar anions.
• Understanding electron attachment energies (eAE) and dipole moments is crucial for predicting anion formation.

Purpose of the Study:

• To calculate eAEs and dipole moments for over 80 carbon chain neutral molecules and their anions.
• To assess the stability and interstellar detectability of these anions.

Main Methods:

• Utilized ab initio quantum chemical methods for calculations.
• Theoretically estimated dipole moments for neutral species and their corresponding anions.

Main Results:

• Calculated eAEs and dipole moments for numerous carbon chain molecules (C_n, C_nX, HC_nN).
• Found anions to be significantly more stable than their neutral counterparts in most cases.
• Identified specific anion groups (e.g., C_2nO^-, C_2nS^-, HC_2nN^-) as promising candidates for astronomical detection.

Conclusions:

• High eAEs and large dipole moments of neutral species correlate with high anion detectability in the interstellar medium.
• Specific carbon chain anions are excellent targets for future astronomical observations and detection.