33S hyperfine interactions in H2S and SO2 and revision of the sulfur nuclear magnetic shielding scale

Trygve Helgaker; Jürgen Gauss; Gabriele Cazzoli; Cristina Puzzarini

doi:10.1063/1.4849177

33S hyperfine interactions in H2S and SO2 and revision of the sulfur nuclear magnetic shielding scale

J Chem Phys. 2013 Dec 28;139(24):244308. doi: 10.1063/1.4849177.

Authors

Trygve Helgaker¹, Jürgen Gauss², Gabriele Cazzoli³, Cristina Puzzarini³

Affiliations

¹ Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, N-0315 Oslo, Norway.
² Institut für Physikalische Chemie, Universität Mainz, D-55099 Mainz, Germany.
³ Dipartimento di Chimica "Giacomo Ciamician," Università di Bologna, Via Selmi 2, I-40126 Bologna, Italy.

PMID: 24387371
DOI: 10.1063/1.4849177

Abstract

Using the Lamb-dip technique, the hyperfine structure in the rotational spectra of H2(33)S and (33)SO2 has been resolved and the corresponding parameters--that is, the sulfur quadrupole-coupling and spin-rotation tensors--were determined. The experimental parameters are in good agreement with results from high-level coupled-cluster calculations, provided that up to quadruple excitations are considered in the cluster operator, sufficiently large basis sets are used, and vibrational corrections are accounted for. The (33)S spin-rotation tensor for H2S has been used to establish a new sulfur nuclear magnetic shielding scale, combining the paramagnetic part of the shielding as obtained from the spin-rotation tensor with a calculated value for the diamagnetic part as well as computed vibrational and temperature corrections. The value of 716(5) ppm obtained in this way for the sulfur shielding of H2S is in good agreement with results from high-accuracy quantum-chemical calculations but leads to a shielding scale that is about 28 ppm lower than the one suggested previously in the literature, based on the (33)S spin-rotation constant of OCS.