Mid-infrared optical properties of vapor-condensed magnesium silicates

Abstract

Amorphous films with the compositions MgSiO3 and Mg2SiO4 were condensed by reactively sputtering cathodes with the compositions MgSi and Mg2Si in argon-oxygen atmospheres. Optical constants for these films in the 7-33 micron region were derived by fitting the transmission curves with harmonic oscillators (classical dispersion theory). Extinction properties of Rayleigh particles with the given compositions were calculated, and the results compare favorably with astronomical data.