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Updated: Jun 26, 2026

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
What makes the huge 31P-31P coupling constants in S(PF2)2 and Se(PF2)2 vary so much with temperature?
Anthony M Reilly1, Derek A Wann, David W H Rankin
1School of Chemistry, University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, UK.
Abstract:
The enormous temperature dependence of the (2)J(PP) coupling constants in S(PF(2))(2) and Se(PF(2))(2) has been explained by a theoretical investigation of their conformations and NMR coupling constants. In contrast, the coupling in O(PF(2))(2) is almost invariant. Gas electron diffraction data for S(PF(2))(2) have been reinterpreted. The results show that two conformers, with C(s) and C(2v) symmetry, exist for the S and Se compounds. The C(s) and C(2v) conformers have very different (2)J(PP) coupling constants (-12.6 and 395.2 Hz for S(PF(2))(2) at B3LYP/aug-cc-pVQZ) and thermal interconversion of these conformers explains the experimental behavior.
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