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Updated: Aug 21, 2025

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
Dissecting conjugation and electronic effects on the linear and non-linear optical properties of rhenium(I) carbonyl
Ricardo J Fernández-Terán1,2, Estefanía Sucre-Rosales3, Lorenzo Echevarria3,4
1Department of Chemistry, University of Sheffield, Sheffield S3 7HF, UK. Ricardo.Fernandez@sheffield.ac.uk.
Abstract:
Herein, we report a theoretical and experimental analysis of the conjugation and electronic effects on the one-photon (1PA) and two-photon absorption (2PA) properties of a series of Re(I) carbonyl complexes with terpyridine-based ligands. An excellent agreement was obtained between the calculated and experimental 2PA spectra of the κ2N-terpyridine tricarbonyl complexes (1a-b), with 2PA cross sections reaching up to ca. 40 GM in DMF. By stepwise lowering the conjugation length in the terpy ligand and changing the local symmetry around the metal centre, we show that conjugation and delocalisation play a major role in increasing 2PA cross sections, and that the character of the excited states does not directly enhance the non-linear properties of these complexes-contrary to the results observed in 1PA. Altogether, these results give valuable guidelines towards more efficient two-photon-absorbing coordination complexes of Re(I), with potential applications in photodynamic therapy and two-photon imaging.
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