title: Silicon Oxysulfide, OSiS: Rotational Spectrum, Quantum-Chemical Calculations, and Equilibrium Structure.
abstract: Silicon oxysulfide, OSiS, and seven of its minor isotopic species have been characterized for the first time in the gas phase at high spectral resolution by means of Fourier transform microwave spectroscopy. The equilibrium structure of OSiS has been determined from the experimental data using calculated vibration-rotation interaction constants. The structural parameters (rO-Si = 1.5064 Å and rSi-S = 1.9133 Å) are in very good agreement with values from high-level quantum chemical calculations using coupled-cluster techniques together with sophisticated additivity and extrapolation schemes. The bond distances in OSiS are very short in comparison with those in SiO and SiS. This unexpected finding is explained by the partial charges calculated for OSiS via a natural population analysis. The results suggest that electrostatic effects rather than multiple bonding are the key factors in determining bonding in this triatomic molecule. The data presented provide the spectroscopic information needed for radio astronomical searches for OSiS.
authors: †I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937 Köln, Germany.
authors: Sven
authors: S
authors: Thorwirth
authors: ‡Institut für Physikalische Chemie, Universität Mainz, 55099 Mainz, Germany.
authors: Leonie Anna
authors: LA
authors: Mück
authors: ‡Institut für Physikalische Chemie, Universität Mainz, 55099 Mainz, Germany.
authors: Jürgen
authors: J
authors: Gauss
authors: §Dipartimento di Chimica Fisica e Inorganica, Università di Bologna, Viale del Risorgimento 4, I-40136 Bologna, Italy.
authors: Filippo
authors: F
authors: Tamassia
authors: ∥Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, United States.|⊥School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States.
authors: Valerio
authors: V
authors: Lattanzi
authors: ∥Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, United States.|⊥School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States.
authors: Michael C
authors: MC
authors: McCarthy
keywords: bonding; equilibrium structure; quantum-chemical calculations; radio astronomy; rotational spectroscopy