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arXiv · 2507.22598

The multiconfigurational ground state of a diradicaloid characterized at the atomic scale

Elia Turco·Lara Tejerina·Gonçalo Catarina·Andres Ortega-Guerrero·Nils Krane·Leo Gross·Michal Juríček·Shantanu Mishra
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Abstract

We report the tip-induced generation and scanning probe characterization of a singlet diradicaloid, consisting of two phenalenyl units connected by an sp-hybridized C$_{4}$ chain, on an ultrathin insulating NaCl surface. The bond-order contrast along the C$_{4}$ chain measured by atomic force microscopy and mapping of charge-state transitions by scanning tunneling microscopy, in conjunction with multiconfigurational calculations, reveal that the molecule exhibits a many-body ground state. Our study experimentally demonstrates the manifestation of strong electronic correlations in the geometric and electronic structures of a single molecule.

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Elia Turco, Lara Tejerina, Gonçalo Catarina, Andres Ortega-Guerrero, Nils Krane, Leo Gross, Michal Juríček, Shantanu Mishra. 2025-07-30. The multiconfigurational ground state of a diradicaloid characterized at the atomic scale. https://doi.org/10.1021/jacs.5c13039

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