keywords: Astrochemistry, column density, dipole moment, interstellar molecule, periodic trends
Investigation of the physical and chemical conditions of the different molecular clouds requires accurate knowledge of the abundances and distributions of the various molecules. Abundances of interstellar and circumstellar species are vital parameters for astronomical and astrophysical models. These abundances rely on the dipole moments of the molecules. The more accurate the dipole moments are, the more reliable the estimated abundances resulting in highly plausible models. The linear carbon chain molecule, C3S with singlet ground state has been astronomically observed by three different sets of researchers with each of them using a different dipole moment to calculate the column density, thus resulting in different column density for the same molecule even from the same astronomical source, thereby posing a constraint on the use of these values for astronomical and astrophysical models. This article reports theoretically calculated dipole moment for this molecule with excellent agreement with the experimentally measured value which could be used in estimating accurate column abundance for this molecule. Recalculation of the abundance of this molecule is necessary due to the difference in the values of the dipole moments previously used in estimating the abundance of C3S.
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