Switchable Valence States in Dinuclear Cobalt Complexes: The Role of Halogenated Catecholates and Counterions.

ABSTRACT: We present the synthesis and comprehensive characterization of a series of eight dinuclear cobalt complexes, C1-C8, with the general formula [Co₂(L)-(X₄cat)₂]²⁺(A)_{1- 2}, wherein X = Br or Cl, A = SO₄ ^2-, ClO₄ ^-, PF^6-, or B-(Ph)₄ ^-, and L denotes a redox inactive bis-tetradentate bridging ligand. Single-crystal X-ray diffraction at 120 K confirms a low-spin Co-(III) configuration in all compounds. SQUID magnetometry also shows that the complexes remain diamagnetic below room temperature. However, the complexes bearing sulfate anions, C1 and C5, exhibit a distinct thermally induced valence tautomeric transition above

SUBMITTER: Hieke TW 

PROVIDER: S-EPMC12268467 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature