Evolution of Fullerenes in Circumstellar Envelopes by Carbon Condensation: Insights from Reactive Molecular Dynamics Simulations
arXiv:2310.17095 · doi:10.1093/mnras/stad2754
Abstract
Fullerenes, including \ce{C60} and \ce{C70}, have been detected in various astronomical environments. Understanding how their structures evolve over time is essential for gaining insights into their life cycle and making further observations. To address this, we conducted reactive molecular dynamics simulations to investigate the evolution of fullerenes in the circumstellar envelopes surrounding carbon-rich asymptotic giant branch stars. Our simulations employed a bottom-up chemistry scheme, wherein fullerenes grow by absorbing and condensing small carbon-based molecules. The results revealed the formation of different structures through heterogeneous reactions based on hydrogen concentration, leading to the emergence of onion-like nanostructures or single-layer fullerenes. To examine the impact of these structural changes on the infrared emission characteristics of fullerenes, we performed quantum chemical calculations. The results indicate that as fullerenes grow larger, additional emission features are introduced in the infrared spectrum. Moreover, two-layered fullerenes show noticeable blue-shift or weakening effects on the bands associated with out-of-plane vibration modes.
References in corpus (40)
- 2021 Census of Interstellar, Circumstellar, Extragalactic, Protoplanetary Disk, and Exoplanetary Molecules
- The evolution of amorphous hydrocarbons in the ISM: dust modelling from a new vantage point
- Formation of buckminsterfullerene (C60) in interstellar space
- C in Reflection Nebulae
- Formation of fullerenes in H-containing Planetary Nebulae
- Evolution of PAHs in photodissociation regions: Hydrogenation and charge states
- Top-down formation of fullerenes in the interstellar medium
- Interstellar C60+
- Global 3D radiation-hydrodynamics models of AGB stars. Effects of convection and radial pulsations on atmospheric structures
- Warm water vapour in the sooty outflow from a luminous carbon star
- Chemical equilibrium in AGB atmospheres: Successes, failures, and prospects for small molecules, clusters, and condensates
- The formation of cosmic fullerenes from arophatic clusters
- Physical Properties of Fullerene-containing Galactic Planetary Nebulae
- Detection of C60 in embedded young stellar objects, a Herbig Ae/Be star and an unusual post-AGB star
- Carbonaceous molecules in the oxygen-rich circumstellar environment of binary post-AGB stars: C_{60} fullerenes and polycyclic aromatic hydrocarbons
- H2 formation on interstellar grains and the fate of reaction energy
- Detection of Buckminsterfullerene emission in the diffuse interstellar medium
- H2 formation on PAHs in photodissociation regions: a high-temperature pathway to molecular hydrogen
- Atmospheric dynamics in carbon-rich Miras. I. Model atmospheres and synthetic line profiles
- Failure of hydrogenation in protecting polycyclic aromatic hydrocarbons from fragmentation
- The chemistry of cosmic dust analogues from C, C, and CH in C-rich circumstellar envelopes
- Machine-learning prediction of infrared spectra of interstellar polycyclic aromatic hydrocarbons
- The aromatic Universe
- Infrared spectroscopy of fullerene C60/anthracene adducts
- C in Photodissociation Regions
- Adsorption of Organic Molecules on Onion-Like-Carbons: Insights on the Formation of Interstellar Hydrocarbons
- Formation of interstellar complex polycyclic aromatic hydrocarbons: Insights from molecular dynamics simulations of dehydrogenated benzene
- On Buckyonions as an Interstellar Grain Component
- Absolute evaporation rates of non-rotating neutral PAH clusters
- Molecular hydrogen formation on interstellar PAHs through Eley-Rideal abstraction reactions
- How Much Graphene in Space?
- Selective Conduction of Organic Molecules via Free-Standing Graphene
- Fragmentation and isomerization of polycyclic aromatic hydrocarbons in the interstellar medium: coronene as a case study
- Infrared action spectroscopy of doubly charged PAHs and their contribution to the aromatic infrared bands
- Nucleation and stabilization of carbon-rich structures in interstellar media
- Machine-learning identified molecular fragments responsible for infrared emission features of polycyclic aromatic hydrocarbons
- Machine Learning interpretation of the correlation between infrared emission features of interstellar polycyclic aromatic hydrocarbons
- Top-down formation of ethylene from fragmentation of superhydrogenated polycyclic aromatic hydrocarbons
- Catalytic role of HI in the interstellar synthesis of complex organic molecule
- Trapping molecules in a covalent graphene-nanotube hybrid