Ionic and Neutral Species in Pulse Radiolysis of Supercritical CO2. 1. Transient Absorption Spectroscopy, Electric Field Effect, and Charge Dynamics

Autor: Myran C. Sauer, Ilya A. Shkrob, Kenji Takahashi, Charles D. Jonah
Rok vydání: 2002
Předmět:
Zdroj: The Journal of Physical Chemistry A. 106:11855-11870
ISSN: 1520-5215
1089-5639
Popis: Transient absorption spectroscopy was used to study the mechanism for radiolysis of dense, liquidlike supercritical (sc) CO2 (T = 41 °C, ρ = 0.84 g/cm3). The 350−1500 nm spectra are decomposed into the contributions from the solvent radical cation, solvent radical anion, and a long-lived neutral product that we associate with singlet carbon trioxide, CO3(1A1). These three species are characterized by their optical spectra, chemical behavior, kinetics, and the response of these kinetics to external electric field. The following mechanism for radiolysis of sc CO2 is suggested: Ionization of the solvent yields ≈5 pairs per 100 eV. Most of these pairs are comprised of the solvent hole and a thermalized quasifree electron; the prompt yield of CO3- is
Databáze: OpenAIRE