Spectral Characterization for Small Clusters of Silicon and Oxygen: SiO,
SiO3, Si2O3, & Si2O4
Infrared spectra of evolved stars have a rise in signal between the 7.0
μm and 8.0 μm wavelengths; the antisymmetric Si−O stretches of small
silicon oxide clusters fall in this range and have large intensities.
Hence, this quantum chemical analysis provides data for such molecules
that may be of significance for astrochemical classification and could
play a role in the formation or degradation of mineral nanocrystals from
or into their constituent atoms. Both explicitly computed anharmonic
fundamental vibrational frequencies and those determined from scaled
harmonic frequencies agree well with known experimental data, and
spectroscopic constants are provided herein such that astronomical
rotational spectral characterization may also be possible for the C2v
SiO3 and Si2O3 molecules.