Related papers: Mapping the structural diversity of C60 carbon clu…
By applying quantum chemical calculation, interstellar infrared spectrum was categorized to three classes. Type-A show unusual feature of strong peaks at 11.3,12.9, and 14.0 micrometer. Usually observed 6.2, 7.7, and 8.6 micrometer bands…
This study explores the molecular origins of plateaus and continuum underlying IR and FIR bands emitted by compact nebulae, especially proto-planetary nebulae. Computational organic chemistry codes are used to deliver the vibrational…
This work aims at exploring the potential energy surfaces of C$_{24}$H$_n${n=0,6,12,18,24} up to 20-25\,eV using the genetic algorithm in combination with the density functional based tight binding (DFTB) potential. The structural diversity…
Recent infrared spectroscopic observations have shown that proto-planetary nebulae (PPNs) are sites of active synthesis of organic compounds in the late stages of stellar evolution. This paper presents a study of Spitzer/IRS spectra for a…
Computational chemistry is used here to build a set of carbonaceous structures whose combined spectra approximately mimic typical UIB (Unidentified Infrared Band) spectra. A large number of relatively small hydrocarbon structures,…
We study the relation between the chemical composition and the type of dust present in a group of 20 Galactic planetary nebulae (PNe) that have high quality optical and infrared spectra. The optical spectra are used, together with the best…
The high interstellar abundances of polycyclic aromatic hydrocarbons (PAHs) and their size distribution are the result of complex chemical processes implying dust, UV radiation, and the main gaseous components (H, C+, and O). These…
We present a study of 16 PNe where fullerenes have been detected in their Spitzer spectra. This large sample of objects offers an unique opportunity to test conditions of fullerene formation and survival under different metallicity…
We report the first detection of buckminsterfullerene (C60) in a proto-planetary nebula (PPN). The vibrational transitions of C60 at 7.0, 17.4, and 18.9um are detected in the Spitzer/IRS spectrum of IRAS 01005+7910. This detection suggests…
In the early 90s, C60+ was proposed as the carrier of two diffuse interstellar bands (DIBs) at 957.7 and 963.2 nm, but a firm identification still awaits gas-phase spectroscopic data. Neutral C60, on the other hand, was recently detected…
The C60 molecule has been recently detected in a wide range of astrophysical environments through its four active intramolecular vibrational modes (T1u) near 18.9, 17.4, 8.5, and 7.0 microns. The strengths of the mid-infrared emission bands…
We present ten new Spitzer detections of fullerenes in Magellanic Cloud Planetary Nebulae, including the first extragalactic detections of the C70 molecule. These new fullerene detections together with the most recent laboratory data permit…
The main goal of this thesis is to unveil some questions related to the formation of complex fullerene-based molecules in space, with the aim of resolving some key problems in astrophysics. The unexpected detections of fullerenes and…
In this study, we explore the characteristics of carbon stars within our Galaxy through a comprehensive analysis of observational data spanning visual and infrared (IR) bands. Leveraging datasets from IRAS, ISO, Akari, MSX, 2MASS, WISE,…
Astronomical dust molecule of carbon-rich nebula-Lin49 and nebula-Tc1 could be identified to be polycyclic-pure-carbon C23 by the quantum-chemical calculation. Two driving forces were assumed. One is high speed proton attack on…
We performed multiwavelength observations of the young planetary nebula (PN) M1-11 and obtained its elemental abundances, dust mass, and the evolutionary status of the central star. The AKARI/IRC, VLT/VISIR, and Spitzer/IRS spectra show…
Fullerenes have been observed in several astronomical objects since the discovery of C$_{60}$ in the mid-infrared (mid-IR) spectrum of the planetary nebula (PN) Tc 1. It has been suggested that the carriers of the broad unidentified…
We present a computational study of assembling carbon clusters and nanophases in space from carbon aggregations. Geometry optimizations and Density-functional-based tight-binding (SCC-DFTB) dynamics methods are employed to predict carbon…
The B36N36 fullerene-like cage structure was proposed as candidate structure for the single-shell boron-nitride cages observed in electron-beam irradiation experiment. We have performed all electron density functional calculations, with…
We compare and analyze the Spitzer mid-infrared spectrum of three fullerene-rich planetary nebulae in the Milky Way and the Magellanic Clouds; Tc1, SMP SMC16, and SMP LMC56. The three planetary nebulae share many spectroscopic similarities.…