Global variational calculations of high-resolution rovibrational spectra: isotopic effects, intensity anomalies and experimental confirmations for H2S, HDS, D2S molecules

Variational calculations of high-resolution infrared molecular spectra for isotopically substituted triatomic molecules from potential and dipole moment functions are discussed. A study of intensity anomalies and of their isotopical behavior especially for symmetry-breaking substitutions represents a particularly interesting subject. Extreme manifestations of intensity anomalies present in spectra of the hydrogen sulfide molecule are considered. A first qualitative experimental confirmation of reported theoretical results for deuterium containing species is discussed.