Polycyclic aromatic hydrocarbons, carbon nanoparticles and the diffuse interstellar bands
Related Experiment Video
Updated: Jul 18, 2026

Characterization, Quantification and Compound-specific Isotopic Analysis of Pyrogenic Carbon Using Benzene Polycarboxylic Acids (BPCA)
Published on: May 16, 2016
1Physics Department, University of Waterloo, Ontario, Canada N2L 3G1. wwduley@uwaterloo.ca
Abstract:
Observational data on the appearance and properties of the diffuse interstellar bands (DIBs) are reviewed in the context of a model in which the proposed carriers of these bands are large carbon molecules and carbon nanoparticles containing between 30 and several hundred carbon atoms. The abundance of these carriers, as estimated from the observed strengths of the DIBs, place strong constraints on their rates of formation and destruction, and suggest that the strongest bands, including that at 4428 A, could be produced via the decomposition of larger carbon particles, possibly those particles that have been postulated to be the source of the 2175 A extinction feature. Such particles are of mixed sp2 and sp3 carbon composition, with sizes between that of large molecules and small macroscopic solids. Any description of their characteristics must combine aspects of molecular and condensed matter physics, and this is incorporated in the present discussion. I discuss recent experimental and theoretical data related to these matters.
More Related Videos
Related Concept Videos
NMR Spectroscopy of Aromatic Compounds
Aromatic Hydrocarbon Anions: Structural Overview
Due to the absence of continuous overlap of p...
π Electron Effects on Chemical Shift: Aromatic and Antiaromatic Compounds
Aromatic Hydrocarbon Cations: Structural Overview
Removing one hydrogen from the intervening CH2 group with both...
IR Absorption Frequency: Hybridization
Among the sp, sp2, and sp3 hybridized orbitals, sp orbitals have the maximum s character (50%). Consequently, the electrons are held more closely to the nucleus, resulting in stronger and shorter C–H bonds that stretch at a...
Five-Membered Heterocyclic Aromatic Compounds: Overview

