Redox reactions and the optical properties of interstellar grains

Abstract

view Abstract Citations (22) References (36) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Redox reactions and the optical properties of interstellar grains. Duley, W. W. Abstract The role of surface and photochemical reactions on the oxidation state of interstellar grain material is examined. The equilibrium in the Fe oxide series (Fe, FeO, Fe3O4, Fe2O3) as a function of ambient conditions is investigated showing primarily that pure Fe grains are unlikely to exist in H I regions because of low temperature oxidation to Fe oxides by O atoms. In addition, it is found that several optical effects usually ascribed to size changes in interstellar grains can be interpreted in terms of chemically induced modifications in the optical properties of the grains. The optical properties of a silicon oxide series SiO(x) is used to study a possible relationship between refractive index variations and variations in the wavelength of maximum linear polarization, suggesting that reduction of silicate or oxide grains in H II regions may be related to OH and H2O maser sources in these regions. Publication: The Astrophysical Journal Pub Date: September 1980 DOI: 10.1086/158308 Bibcode: 1980ApJ...240..950D Keywords: Granular Materials; Interstellar Matter; Optical Properties; Photochemical Reactions; Surface Reactions; H I Regions; H Ii Regions; Interstellar Masers; Iron Oxides; Refractivity; Silicon Oxides; Water Masers; Astrophysics; Interstellar Grains:Chemical Composition full text sources ADS |