Disentangling chemical pressure and superexchange effects in lanthanide-organic valence tautomerism.

ABSTRACT: Valence tautomerism in molecule-based f-block materials remains virtually elusive. As a result, the effects driving and controlling the valence conversion phenomenon are poorly understood. Herein, we unravel these fundamental factors by systematic chemical modification of a bona fide lanthanide coordination solid, SmI₂(pyrazine)₂(tetrahydrofuran), in which a complete, temperature-driven conversion between Sm(ii) and Sm(iii) occurs abruptly around 200 K. Solid solutions incorporating either divalent, diamagnetic metal ions or Sm(iii) ions feature disparate behavior. Substitution with redox-inactive, divalent metal ions invariably leads to lower conversion temperatures and reduced cooperativity. In contrast, incorporation of redox-inactive Sm(iii) ions leads to t

SUBMITTER: Viborg A 

PROVIDER: S-EPMC11921795 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature