Related papers: Termination of bottom-up interstellar aromatic rin…
Evolved stars are primary sources for the formation of polycyclic aromatic hydrocarbons (PAHs) and dust grains. Their circumstellar chemistry is usually designated as either oxygen-rich or carbon-rich, although dual-dust chemistry objects,…
Understanding how the $\mathrm{H}_2$ molecule is formed under the chemical conditions of the interstellar media (ISM) is critical to the whole chemistry of it. Formation of $\mathrm{H}_2$ in the ISM requires a third body acting as a…
As the only moon in the solar system with a thick atmosphere, Titan is a compelling and enigmatic world containing a complex organic haze. Polycyclic aromatic hydrocarbon (PAH) molecules are believed to play an essential role in the…
We present a model for the hydrogenation states of Polycyclic Aromatic Hydrocarbons (PAHs) in the diffuse interstellar medium. First, we study the abundance of hydrogenation and charge states of PAHs due to photo-ionization,…
In interstellar environment, fullerene species readily react with large molecules (e.g., PAHs and their derivatives) in the gas phase, which may be the formation route of carbon dust grains in space. In this work, the gas-phase ion-molecule…
The cosmic-ray ionization rate ($\zeta$, s$^{-1}$) plays an important role in the interstellar medium. It controls ion-molecular chemistry and provides a source of heating. Here we perform a grid of calculations using the spectral synthesis…
The formation of complex organic molecules in the interstellar medium (ISM) is central to astrochemistry and prebiotic chemistry, as these species may act as precursors to biomolecules essential for life. Although glyceraldehyde…
It is long debated if pre-biotic molecules are indeed present in the interstellar medium. Despite substantial works pointing to their existence, pre-biotic molecules are yet to be discovered with a complete confidence. In this paper, our…
[Abridged] Ethylene oxide and its isomer acetaldehyde are important complex organic molecules because of their potential role in the formation of amino acids. Despite the fact that acetaldehyde is ubiquitous in the interstellar medium,…
Methane is typically thought to be formed in the solid state on the surface of cold interstellar icy grain mantles via the successive atomic hydrogenation of a carbon atom. In the current work we investigate the potential role of molecular…
Polycyclic aromatic hydrocarbons (PAHs) are among the most ubiquitous compounds in the universe, accounting for up to ~25% of all interstellar carbon. Since most unsubstituted PAHs do not possess permanent dipole moments, they are invisible…
Context: PAHs are thought to be a ubiquitous and important dust component of the interstellar medium. However, the effects of their immersion in a hot (post-shock) gas have never before been fully investigated. Aims: We study the effects of…
We examine the annihilation of positrons on polycyclic aromatic hydrocarbon (PAH) molecules in interstellar medium conditions. We estimate the annihilation rates of positrons on PAHs by a semi-empirical approach. We show that PAHs can play…
Hydrocarbons play a key role in shaping the chemistry of the interstellar medium (ISM), but their enrichment and relationship with carbonaceous grains and polycyclic aromatic hydrocarbons (PAHs) still lack clear observational constraints.…
It has been shown that the diversity of the aromatic emission features can be rationalized into different classes of objects, in which differences between circumstellar and interstellar matter are emphasised. We probe the links between the…
We investigate the relative efficiencies of low-temperature chemical reactions in the Interstellar medium (ISM) with H$^-$ anion reacting in the gas phase with cyanopolyyne neutral molecules, leading to the formation of anionic C$_x$N$^-$…
The formation of methanol (CH3OH) on icy grain mantles during the star formation cycle is mainly associated with the CO freeze-out stage. Yet there are reasons to believe that CH3OH also can form at an earlier period of interstellar ice…
Reactions between cyano radical and aromatic hydrocarbons are believed to be important pathways for the formation of aromatic nitriles in the interstellar medium (ISM) including those identified in the Taurus molecular cloud (TMC-1).…
Polycyclic aromatic hydrocarbons (PAHs) are key dust components in galaxies and play a fundamental role in the physics of the interstellar medium (ISM), yet their response to AGN feedback remains debated. We present a spatially resolved…
Many complex organic molecules and inorganic solid-state compounds have been observed in the circumstellar shell of stars (both C-rich and O-rich) in the transition phase between Asymptotic Giant Branch (AGB) stars and Planetary Nebulae…