Efficient Chirality-Induced Spin Selectivity in Self-Assembled Monolayers of Ru <sub>2</sub> <sup>5</sup> <sup>+</sup> Paddlewheel Complexes
High Resolution Image Download MS PowerPoint Slide The use of coordination compounds provides a promising strategy to unravel the factors governing chirality-induced spin selectivity (CISS), particularly the contribution of spin–orbit coupling (SOC) to its magnitude. Here, we report the formation of self-assembled monolayers on gold substrates of a chiral paramagnetic Ru 2 5+ paddlewheel complex, [Ru 2 (NCS){μ-( S )- or ( R )-pycsa} 2 (μ-OAc) 2 ] (pycsa = N -(pyridin-2-yl)-10-camphorsulfonamidate), denoted as ( S )- or ( R )- RuNCS . The incorporation of camphor groups confers point chirality to the molecule and causes a slight twisting around the Ru 2 unit, introducing also a helical chirality, as evidenced by single-crystal X-ray diffraction and dichroic electronic absorption. The complex features an axial ligand bearing a terminal sulfur atom that serves as a robust anchoring site to the metallic surface. The resulting SAMs are homogeneous, stable, and exhibit very reproducible electrical characteristics. Magnetic-conductive atomic force microscopy measurements on enantiopure Ni/Au– RuNCS junctions reveal remarkable spin polarizations reaching values from 60 to 80%, which is particularly noteworthy considering the monolayer nature of the film and the modest helicity of the paddlewheel motif.
Authors
- Mathieu Gonidec (ORCID: https://orcid.org/0000-0002-0187-1305)
- Elizabeth A. Hillard (ORCID: https://orcid.org/0000-0002-5149-0324)
- Niccolò Giaconi (ORCID: https://orcid.org/0000-0003-2118-8308)
- Gilles Pécastaings (ORCID: https://orcid.org/0000-0002-9109-6225)
- Miguel Cortijo (ORCID: https://orcid.org/0000-0002-3970-0720)
- Santiago Herrero (ORCID: https://orcid.org/0000-0002-9901-1142)
- Patrick Rosa (ORCID: https://orcid.org/0000-0001-5670-2624)
- Matteo Mannini (ORCID: https://orcid.org/0000-0001-7549-2124)
- Lorenzo Poggini (ORCID: https://orcid.org/0000-0002-1931-5841)
- Isabel Coloma (ORCID: https://orcid.org/0000-0002-4969-9479)
- Thierry Buffeteau
- Francesco Parmeggiani
Institutions
- Universidad Complutense de Madrid (ES)
- Centre National de la Recherche Scientifique (FR)
- Université de Bordeaux (FR)
- Institut des Sciences Moléculaires (FR)
- Knowledge Systems Institute (US)
- Institut de Chimie de la Matière Condensée de Bordeaux (FR)
- Institute for the Chemistry of OrganoMetallic Compounds (IT)
- Centre de recherche Paul Pascal (FR)
- Public Knowledge (US)
- Institut Polytechnique de Bordeaux (FR)
- University of Florence (IT)
Publication Details
- Journal
- Journal of the American Chemical Society
- Published
- 2026-06-27
- DOI
- https://doi.org/10.1021/jacs.6c02811
- Primary Topic
- Magnetism in coordination complexes
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Banco Santander
- Comunidad de Madrid
- Agence Nationale de la Recherche
- Universidad Complutense de Madrid
- Université de Bordeaux
- Ministero dell'Università e della Ricerca
- European Research Council